SPENGLER, E. H. (1955). Introduction to Business. McGraw-Hill Book Company.
Lua i Stíl Chicago (17ú heag.)SPENGLER, Edwin H. Introduction to Business. McGraw-Hill Book Company, 1955.
Lua MLA (8ú heag.)SPENGLER, Edwin H. Introduction to Business. McGraw-Hill Book Company, 1955.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.