APA引文

(1994). Project learning tree: Environmental education activity guide (2nd.). Project Learning Tree.

Chicago Style (17th ed.) Citation

Project Learning Tree: Environmental Education Activity Guide. 2nd. Washington: Project Learning Tree, 1994.

MLA引文

Project Learning Tree: Environmental Education Activity Guide. 2nd. Project Learning Tree, 1994.

警告：這些引文格式不一定是100％准確.