I understand why part of the Hermeneia Commentary Series is under "Bible Commentary" while other portions are under "Commentary". This is an implementation of the Logos sense of canon. But why are portions of Hermeneia Commentaries under "Monographs" for example The Apostolic Tradition: A commentary by Bradshaw et. al. (yes that is from the title page) ... The Critical Edition of Q I can justify as a monograph but ...