1. Technical manual TM (series). 11-2351. Exposure meters PH-77-C, PH-77-D, PH-77-E, PH-252-A, and PH-260, Changes 3; Feb. 4, 1948. Bookmark Corporate/Agency Authors: Army Department and Defense Dept. Publisher: Army Department Date: [1948.] SuDoc number: W 1.35:11-2351/ch.3