Moreover , Gheorghe Duca himself was considered the greatest authority in railways at the end of the 19th century .
Mironescu ( Statistics and Engineering Graphics ) , Constantin Istrati ( Physics ) , or Anghel Saligny ( Bridges and Roads ) .
Gheorghe Duca himself was considered the greatest authority in railways at the end of the 19th century .
Mironescu ( Statistics and Engineering Graphics ) , Constantin Istrati ( Physics ) , or Anghel Saligny ( Bridges and Roads ) .