4American society of civil engineers, ASCE7-05, Minimum Design Load for Buildings and Other Structures[S], 2005.27-28.
5American institute of steel construction, AISC 360-05, Specification for Structural Steel Buildings[S], 2005. 381-383.
6American institute of steel construction, AISC S335-1989, Specification for Structural Steel building-Allowable Stress Design and Plastic Design[S], 54-55.