Columbia subject headings:
Catholic Church--Apologetic works.
Spalding, M. J. (Martin John), 1810-1872.
Harvard subject headings:
Catholic Church--Apologetic works.
Spalding, M. J. (Martin John), 1810-1872.
Princeton subject headings:
Catholic Church--Apologetic works.
Spalding, M. J. (Martin John), 1810-1872.