link.springer.com/article/10.1007/s10800-005-90...
amlett.com/uploads/55a26ce7cea881436708071_full...
cdn.intechopen.com/pdfs-wm/24065.pdf
www.sciencedirect.com/science/article/pii/S1359...

трение
cdn.intechopen.com/pdfs-wm/24065.pdf