The Critical Edition of Q, edited by James M. Robinson, Paul Hoffmann and John S. Kloppenborg and Excavating Q, by John S. Kloppenborg Verbin
Most New Testament scholars believe that besides following the Gospel of Mark's narrative of Jesus's ministry and passion, the authors of Matthew and Luke independently drew from a common collection of Jesus sayings in composing their Gospels. These books represent nearly two decades of study of the theoretical Q by two of its foremost scholars, James Robinson and John Kloppenborg Verbin (whose recent marriage accounts for his added surname).