scientific article published on February 1, 1991

scientific article published in April 1995

scientific article published on August 1991

scientific article published on July 1, 1992

retracted scientific article published on September 1, 1991

scientific article published on June 1, 1992

scientific article

scientific article published in September 1998

scientific article published in March 1995

scientific article published in August 1996

scientific article

scientific article

scientific article published on April 1, 1993

scientific article published on August 1, 1997

retracted scientific article published on August 1993

scientific article published in January 1993

scientific article published in January 1991

scientific article published on December 1, 1992

scientific article published in March 1995

scientific article published in January 1996

scientific article published on October 1, 1992

retracted scientific article published in May 1990

scientific article published on August 1, 1990

scientific article published in May 1994

scientific article

retracted scientific article published on November 1, 1991

scientific article published on October 1, 1998

scientific article

scientific article published in March 2003

scientific article published on January 1, 1992

retracted scientific article published in July 1990

scientific article published on June 1, 1993

retracted scientific article

retracted scientific article published on July 1994

scientific article published in January 2017

scientific article published in March 2017

scientific article published on June 1, 1992

scientific article published on February 1, 1992

scientific article published on January 1, 1992

scientific article published in May 1990

scientific article published on January 1, 1990

retracted scientific article published on July 1, 1992

scientific article published in April 1992

scientific article published on June 1994

scientific article published on 01 March 1996