1997,Nov.=97-13; 1998,Jan.=98-5; 1998,Nov.=98-11; 1999,Nov.=99-11; 2000,Jan.=00-1; 2000,Nov.=00-4; 2001,Jan.=00-1; 2002,Nov.=02-8; 2003,Jan.=03-1; 2004,Aug.=04-2; 2004,Dez.=04-5; 2005,Dez.=05-4; 2006,Jan.=06-1; 2006,Dez.=06-4; 2007,Jan.=07-1; 2007,Dez.=07-3; 2008,Jan.=08-1; 2008,Dez.=08-2; 2009,Dez.=09-1; 2009,Aug.=09-2; 2009,Dez.=09-3; 2010,Jan.=10-1; 2010,Aug.=10-2; 2010,Dez.=10-3; 2011,Jan.=11-3 von:
Texas A&M University. Agricultural and Food Policy Center: AFPC working paper (SLUB)
1998,Update=98-5; 2003,Jan.=03-1; 2006,Aug.=06-3; 2007,Aug.=07-11; 2007,Dez.=07-14; 2008,Jan.=08-1; 2008,Dez.=08-3; 2009,Jan.=09-1; 2009,Aug.=09-3; 2009,Dez.=09-4; 2010,Jan.=10-1; 2010,Aug.=10-2; 2011,Jan.=11-1 von:
Texas A&M University. Agricultural and Food Policy Center: AFPC briefing paper (SLUB)