| from 11/07/2003 to 12/14/2007 in Business Source Premier |
| from 01/06/2003 to present in General OneFile |
| from 01/01/1987 to present in LexisNexis Academic (selected full-text only) |
| from 12/01/1999 to present in ABI/INFORM Global |
| from 03/27/2000 to present in Academic OneFile, Business Source Premier, General OneFile, LexisNexis Academic and MasterFILE Premier |
| from 01/18/2008 to present in Business Source Premier |
| from 05/03/2001 to present in LexisNexis Academic |
| from 01/01/1987 to present in LexisNexis Academic (selected full-text only) |
| from 06/30/2006 to present in LexisNexis Academic |
| from 05/22/2000 to 02/09/2005 in General OneFile |
| from 02/01/2007 to present in Academic OneFile and Literature Resource Center |
| from 10/23/1998 to present in LexisNexis Academic |
| from 12/01/1997 to present in Health Source: Consumer Edition and MasterFILE Premier |
| from 06/01/2001 to present in ProQuest Research Library |
| from 08/01/2001 to present in General OneFile |
| from 01/01/2008 to present in General OneFile |
| from 01/01/1995 to 01/31/1999 in Academic Search Premier and MasterFILE Premier |
| from 05/13/2009 to present in Health Source: Consumer Edition |
| from 01/01/2003 to present in Health Source: Consumer Edition and Health Source: Consumer Edition |
| from 08/03/1984 to 10/27/2005 in Academic OneFile and General OneFile |
| from 01/06/1995 to 10/20/2005 in Business Source Premier |
| from 02/21/2003 to 10/26/2005 in LexisNexis Academic |
| from 10/16/2008 to present in LexisNexis Academic |
| from 10/27/2005 to present in Business Source Premier |
| from 10/27/2005 to 10/15/2008 in LexisNexis Academic |
| from 11/03/2005 to 10/09/2008 in General OneFile |
| from 10/16/2008 to present in General OneFile |
| from 09/07/1995 to 10/09/2008 in Academic OneFile and General OneFile |
| from 03/07/2001 to present in LexisNexis Academic |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 10/01/2003 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 02/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 02/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 10/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 02/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 10/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 10/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 02/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 10/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 07/01/2006 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 01/01/2004 to 06/30/2006 in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 10/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 07/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 01/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 02/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 12/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 04/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| in LexisNexis Academic (selected full-text only) |
| from 08/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 05/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 04/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 11/01/2003 to present in Business Source Premier and MAS Ultra - School Edition |
| from 06/01/2004 to present in Business Source Premier and MAS Ultra - School Edition |
| from 03/01/2004 to present in Business Source Premier, MAS Ultra - School Edition and MasterFILE Premier |
| from 03/01/1992 to 12/31/2003 in Academic Search Premier, Business Source Premier, MAS Ultra - School Edition, MasterFILE Premier and Points of View Reference Center |
| from 07/01/2000 to 05/31/2001 in MasterFILE Premier |
| from 01/01/1999 to 01/10/1999 in LexisNexis Academic (selected full-text only) |
| from 05/01/1990 to present in MAS Ultra - School Edition, MasterFILE Premier and Science Reference Center |
| from 02/01/1993 to 1 month ago in Academic OneFile and General OneFile |
| from 02/01/1994 to present in ProQuest Research Library |
| from 12/01/2003 to present in MAS Ultra - School Edition and MasterFILE Premier |
| from 1937 to 12/31/1977 in PubMed Central |