Παραπομπή APA

Ward ,Martin L. (1977). Sears list of subject headings. The H W Wilson Comp.

Παραπομπή Chicago Style

Ward ,Martin L. Sears List of Subject Headings. London: The H W Wilson Comp, 1977.

Παραπομπή MLA

Ward ,Martin L. Sears List of Subject Headings. The H W Wilson Comp, 1977.