 Some of the manuscripts proposed as belonging to Family 13 appear to have links to Calabria (mss 13, 124, 174, 230) and one to Albania (ms. 1689); manuscripts 124 and 174 being recorded as having been written in Calabria, and most of the family members recording menologion readings for Calabrian saints.Some family members have common supplemental geographical material that appears to derive from a 7th-century original.In 1961, Jacob Geerlings published three monographs (Matthew, Luke, and John) on the family, although some scholars regard this work as flawed by serious methodological problems.