Jackie Gaff. (2005). I Wonder Why Pine Trees Have Needles: And Other Questions About Forests. Gardners Books.
芝加哥风格引文Jackie Gaff. I Wonder Why Pine Trees Have Needles: And Other Questions About Forests. Gardners Books, 2005.
MLA引文Jackie Gaff. I Wonder Why Pine Trees Have Needles: And Other Questions About Forests. Gardners Books, 2005.
警告：这些引文格式不一定是100％准确.