Eleventh progress report of the investigation of prestresse-d reinforced concrete for highway bridges / prepared as a p-art of an investigation conducted by the Engineering Experi-ment Station University of Illinois ; in cooperation with t-he Division of Highway State of Illinois and U.S. Departme-nt of Commerce Bureau of Public Roads 

 - Urbana, Ill. : University of Illinois 
 - [221] p. 
 - Progress report ; no.11 .