scientific article published in January 2004

scientific article published in July 2002

scientific article published in February 2003

scientific article published in April 1998

scientific article published in October 1996

scientific article published in August 1998

scientific article published in April 2019

scientific article published in August 2017

scientific article published in January 2001

working paper published in January 2007

working paper published in October 2008

scientific article published in December 2011

scholarly article published in 2014

scientific article published in December 2006

scientific article published in May 2009

scientific article published in September 2019

scientific article published in June 2007

scientific article published in May 2015

scientific article published in 2012

working paper published in July 2010

scholarly article published in 2014

scientific article published in May 2013

scientific article published in May 2004

scientific article published in November 2002