By Keith, Lawrence H..
New York : Lewis Publishers, 1996 , Incluye 2 disketes. 1566701635

By Patnaik, Pradyot.
EE.UU : Lewis Publishers, 1997 0873719891

By Berk, Sharon G..
Boca Raton, FL : Lewis, 1993 0-87371-623-X

Boca Ratón, FL : IPGRI : | IDRC : | Lewis, 1999 0-88936-884-8, IDRC1-56670-405-7, Lewis

By Rombke, Jörg.
New York : Lewis Publishers, 1996 .
282 p. 0566700701