http://fetweb.ju.edu.jo/staff/che/ymubarak/Strength-lectures/chapter4.pdf
http://www.thermotech.com/pdf/New_DirectGear.pdf
http://www.blogger.com/post-create.g?blogID=7882257832973054232
http://www.freestudy.co.uk/statics/beams/beam%20tut1.pdf
http://www.blogger.com/post-create.g?blogID=7882257832973054232
http://www.assakkaf.com/Courses/ENES220/Lectures/Lecture9%20.pdf
http://freeit.free.fr/Case,Chilver,Ross_Strength_of_Materials&Structures,1999/19206_12.pdf
http://abe.ufl.edu/tburks/Presentations/ABE4171/Stress%20and%20Deformation%20Analysis.pdf
http://www.thermotech.com/pdf/New_DirectGear.pdf
http://www.blogger.com/post-create.g?blogID=7882257832973054232
http://www.freestudy.co.uk/statics/beams/beam%20tut1.pdf
http://www.blogger.com/post-create.g?blogID=7882257832973054232
http://www.assakkaf.com/Courses/ENES220/Lectures/Lecture9%20.pdf
http://freeit.free.fr/Case,Chilver,Ross_Strength_of_Materials&Structures,1999/19206_12.pdf
http://abe.ufl.edu/tburks/Presentations/ABE4171/Stress%20and%20Deformation%20Analysis.pdf