Piedra Constantino, R. d. l. (1997). Evaluation of sustainable production systems in hillsides, La Fraylesca, Chiapas, México.
Chicago Style aipamenaPiedra Constantino, R. de la. Evaluation of Sustainable Production Systems in Hillsides, La Fraylesca, Chiapas, México. 1997.
MLA aipamenaPiedra Constantino, R. de la. Evaluation of Sustainable Production Systems in Hillsides, La Fraylesca, Chiapas, México. 1997.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.