By Gelder, Erich.
Barcelona : Marcombo, 1988 .
68 p. : 21 cm.
8426706991

By Gelder, Erich.
Barcelona : Marcombo, 1988 .
72 p. : 21 cm.
8426707009

By Gelder, Erich.
Barcelona : Marcombo, 1988 .
71 p. : 21 cm.
8426707017

By Camenzind, Hans R..
Florida : Litton Educational Publishing, 1972 .
332 p. : 23 cm.
0882757636

By Malvino, Albert Paul.
Madrid : McGraw-Hill, 1994 .
1048 p. : 25 cm.
8448119991

By Richman, Paul.
México : A.I.D., 1973 .
142 p. : 23 cm.

By Sanborn, Paul.
México : Centro Regional de Ayuda Técnica, 1973 .
508 p. : 22 cm.