Lua APA (7ú heag.)

Plötner, R. (1960). Wilhelm Pieck.

Lua i Stíl Chicago (17ú heag.)

Plötner, Ruth. Wilhelm Pieck. Berlin, 1960.

Lua MLA (8ú heag.)

Plötner, Ruth. Wilhelm Pieck. 1960.

Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.