If your floor really needs more than that, consider a low-cost alternative to refinishing: Apply a fresh topcoat of nonyellowing polyurethane, found in the flooring section of a home improvement store. Be sure to very lightly sand the floors with a pole sander and fine-grit sandpaper.
There are 440 different species of sharks in the world today classified into eight different orders described below with some examples of known sharks species for each group.
This volume presents a fully illustrated field guide for the identification of the sharks and rays most relevant to the fisheries of the Mediterranean and Black Sea. An extensive literature review was carried out for the preparation of this document. A total of 49 sharks, 34 batoids and 1 chimaera. are fully treated.