sentences:  Dealers also vary in the type of material they handle, ranging from a general stock to highly specialised firms who only trade in particular countries or topical areas.Stamp catalogues principally evolved from stamp dealer's price lists, though today most stamp catalogues no longer represent a retail price list.The Stanley Gibbons catalogue is an exception that, in principle, still shows the price at which they would sell a particular stamp over the counter at their London shop, or by mail order, if they had it in stock and it was in the exact condition outlined in the notes at the start of the catalogue.