Grealy, M. D. (1991). Knock: Apparition Gable from 1879 to the present. Cashin Printing Services.
Čikaški stil citiranja (17. izdanje)Grealy, Msgr Dominic. Knock: Apparition Gable from 1879 to the Present. Cashin Printing Services, 1991.
MLA način citiranja (8. izdanje)Grealy, Msgr Dominic. Knock: Apparition Gable from 1879 to the Present. Cashin Printing Services, 1991.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.