Robertson, T. W., & Sardou, V. (1869). Progress: A comedy in three acts. s.n..
Lua i Stíl Chicago (17ú heag.)Robertson, T. W., agus Victorien Sardou. Progress: A Comedy in Three Acts. [S.l.: s.n., 1869.
Lua MLA (8ú heag.)Robertson, T. W., agus Victorien Sardou. Progress: A Comedy in Three Acts. s.n., 1869.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.