Lewis, W. (1976). Peter John Olivi, prophet of the year 2000: Ecclesiology and eschatology in the Lectura super Apocalipsim; introduction to a critical edition of the text.
Chicago-viite (17. p.)Lewis, Warren. Peter John Olivi, Prophet of the Year 2000: Ecclesiology and Eschatology in the Lectura Super Apocalipsim; Introduction to a Critical Edition of the Text. 1976.
MLA-viite (8. p.)Lewis, Warren. Peter John Olivi, Prophet of the Year 2000: Ecclesiology and Eschatology in the Lectura Super Apocalipsim; Introduction to a Critical Edition of the Text. 1976.
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