(1995). Environmental learning for the 21th century. Paris: Organisation for Economic Co-operation and Development.
Παραπομπή Chicago StyleEnvironmental Learning for the 21th Century. Paris: Organisation for Economic Co-operation and Development, 1995.
Παραπομπή MLAEnvironmental Learning for the 21th Century. Paris: Organisation for Economic Co-operation and Development, 1995.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.