Prestwood, E. L., & Campbell, B. H. (1963). Practice in English: A workbook in fundamentals. Houghton, Mifflin Co..
Lua i Stíl Chicago (17ú heag.)Prestwood, Elwood L., agus Bertha Handlan Campbell. Practice in English: A Workbook in Fundamentals. Boston ; New York [etc.]: Houghton, Mifflin Co., 1963.
Lua MLA (8ú heag.)Prestwood, Elwood L., agus Bertha Handlan Campbell. Practice in English: A Workbook in Fundamentals. Houghton, Mifflin Co., 1963.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.