This image is a derivative work of the following images: File:Poutrelle.svg licensed with Cc-by-sa-3.0, GFDL 2008-06-22T21:26:47Z Roulex 45 542x933 (38142
image is a derivative work of the following images: File:Section_modulus-I-beam-weak_axis.svg licensed with PD-self 2011-05-25T18:04:25Z Wizard191 242x207
derivative work of the following images: File:Area_moment_of_inertia_of_a_I-beam.svg licensed with PD-self 2008-11-29T23:24:28Z Zielu20 272x187 (10793 Bytes)