German tug Gerhard 4 built at Rotterdam, Netherlands in 1911 according to the Dutch magazine Scheepvaart dated 10 January 1912

A list of the ships launched in 1911 reported the German tug Gerhard 4 of 40 tons built by Machinefabriek Delftshaven, H. de Ridder, Rotterdam, Netherlands for account of H. Bovermann, Ruhrort, Germany.