Labbé is inconsistent and irregular in method. He seems to have learned to cite titles in the original languages when he was nearly through collecting them. It was too late to change and furthermore his sources probably often gave him Latin and not the original French or Italian titles. For example, he cites a book by Augustinus Superbus by its Latin title and adds the note "Italicè."[64] In the seventeenth century this was an altogether regular way of citing an Italian title. He also cites the same book with an Italian title. In reading the proof he could have removed the duplication. The article on Augustinus Marloratus seems to have been written before he realized the necessity of bringing the author's name into the first place for the purpose of alphabetizing the entries. He is irregular in regard to critical comment, which the plan of his book did not require. He usually adds none, but see, as exceptions, the remarks on Angelus Roccha, Conradus Gesnerus, Conradus Lycosthenes, and Joannes Neander. It will be noticed at once that all but one of these men are Protestants. In a few instances Labbé gives additional information about the subject of the book that he is citing. For example, he adds a paragraph to the citation of a catalogue of heretical writers compiled by Bernardus Luxemburgensis: Regarding these men [i.e., heretical authors] ancient writers ought also to be consulted: Philastrius, Augustine, the author of _Praedestinati_ (edited by Sirmondus), St. Epiphanius, St. John Damascene, and others. This paragraph may indicate that Labbé considered including subjects but did not find a way to do so. Critics of the _Bibliotheca Bibliothecarum_ and among them Adrien Baillet, who should have known better, have called for interpretative and critical comments. They ought to have perceived that such comments, although useful, would have greatly exceeded Labbé's purpose. In all the later history of bibliographies of bibliographies only two men--Gabriel Peignot and Julius Petzholdt--have made a systematic effort to add comments. Labbé does, to be sure, often express his opinion about heretical books, and his warnings have awakened Protestant wrath and have caused Protestant bibliographers to speak harshly of him. He has rarely expressed himself so vigorously as he does in the article "Robertus Cocus" (Robert Cooke, 1550-1615), where he writes: