U-30 , built by the Hungarian firm of Ganz Danubius at Fiume , was launched in December 1916 .
U-30 , built by the Hungarian firm of Ganz Danubius at Fiume , was commissioned in February 1917 .
U-30 , built by the Hungarian firm of Ganz Danubius at Fiume , was launched in December 1916 and commissioned in February 1917 .