Feldt, R., Johnson, L., & Neumann, M. (2002). Ruby developer's guide. Syngress Pub..
芝加哥风格引文Feldt, Robert, Lyle Johnson, 与 Michael Neumann. Ruby Developer's Guide. Rockland, MA: Syngress Pub., 2002.
MLA引文Feldt, Robert, et al. Ruby Developer's Guide. Syngress Pub., 2002.
警告：这些引文格式不一定是100％准确.