Baumann, P. (1970). Collecting antique Marbles. Mid-America Book Company.
Lua i Stíl Chicago (17ú heag.)Baumann, Paul. Collecting Antique Marbles. Leon: Mid-America Book Company, 1970.
Lua MLA (8ú heag.)Baumann, Paul. Collecting Antique Marbles. Mid-America Book Company, 1970.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.