281. Technical news bulletin; [managing editor, R. W. Seward]. Bookmark SuDoc number: C 13.13: (v.nos.&nos.)
282. Technical news bulletin; [managing editor, R. W. Seward]. Bookmark SuDoc number: C 13.13: (v.nos.&nos.)
283. Technical news bulletin; [managing editor, R. W. Seward]. Bookmark SuDoc number: C 13.13: (v.nos.&nos.)
284. Technical news bulletin; [managing editor, R. W. Seward]. Bookmark SuDoc number: C 13.13: (v.nos.&nos.)
285. Technical news bulletin; [managing editor, Sharon L. Butrymowicz]. Bookmark SuDoc number: C 13.13: (v.nos.&nos.)