Faith of Our Fathers, The by James Gibbons (1834 - 1921)

conversion manual in the United States, and by 1980 was in its 111th printing.

(From the preface) “The object of this little volume is to present in a plain and practical form an exposition and vindication of the principal tenets of the Catholic Church. It was thought sufficient to devote but a brief space to such Catholic doctrines and practices as are happily admitted by Protestants, while those that are controverted by them are more elaborately elucidated...

...As his chief aim has been to bring home the truths of the Catholic faith to our separated brethren, who generally accept the Scripture as the only source of authority in religious matters, he has endeavored to fortify his statements by abundant reference to the sacred text. He has thought proper, however, to add frequent quotations from the early Fathers, whose testimony, at least as witnesses of the faith of their times, must be accepted even by those who call in question their personal authority.” (Summary from Wikipedia with quotes from the preface of this volume.)