I remember reading some forum discussions where certain resources within the same series were designated either "Monograph" or "Bible Commentary" based on certain ways the author approached their writing (or whatever else). But it's possible that all volumes in the "Christ-Centered Exposition Commentary" should be of type "Bible Commentary" (since that's actually in the series name) and since, at least on a surface level, they seem to adopt a similar approach. However, the Jeremiah/Lamentations volume and the Psalms 51-100 volume are designated as type "Monograph".
Likewise, Pass It On: A Bible Commentary for Laymen: First and Second Timothy and Themes from Romans by Robert Mounce (both in the "A Bible Commentary for Laymen" series) are designated as a Monograph but they also seem they could be Bible Commentary types.
