Dyfyniad APA
ebrary, Inc, & Kelleher, N. B. (2012). U.S. oil sources: Turmoil and tranquility. Nova Science Publishers.
Dyfyniad Arddull Chicago
ebrary, Inc, and Natalie B. Kelleher. U.S. Oil Sources: Turmoil and Tranquility. Hauppauge, N.Y.: Nova Science Publishers, 2012.
Dyfyniad MLA
ebrary, Inc, and Natalie B. Kelleher. U.S. Oil Sources: Turmoil and Tranquility. Nova Science Publishers, 2012.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.