Bossing, N. L. (1944). Progressive methods of teaching in secondary school. Houghton Mifflin.
Lua i Stíl Chicago (17ú heag.)Bossing, Nelson L. Progressive Methods of Teaching in Secondary School. Houghton Mifflin, 1944.
Lua MLA (9ú heag.)Bossing, Nelson L. Progressive Methods of Teaching in Secondary School. Houghton Mifflin, 1944.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.