WBirds of East AsiaWCollins Bird GuideWA Field Guide to the Birds of Hawaii and the Tropical PacificWA Guide to the Birds of Mexico and Northern Central AmericaWGulls of Europe, Asia and North AmericaWA Photographic Guide to the Birds of IndonesiaWThe Pocket Guide to British BirdsWThe Sibley Guide to Bird Life & BehaviorWThe Sibley Guide to Birds