Hi,
to understand this designer series,he began from D1 to D25,as his work in France and Russian,and,when he return to France,he began with Type-1 (D26),maybe a fighter but not sure,the Type-2 (D27) was a well known fighter,the Type-3 was alternative design to a 1918 C.1 competition,but not built,the CAN.2 design was Type-4,the Type-5 to Type-15 are not known,but certainly a light and heavy bombers were in it,DB.16 & DB.17 was also called Type-16 & Type-17,after that he retired from designing aircraft in 1925.