There are different claims to the origins of the ugg boot style. Artisanal sheepskin boots were known in rural Australia during the 1920s, and were reportedly worn by shearers as they found them resistant to wool yolk (Lanolin), which would rot their ordinary boots. However, the date of commercial manufacturing began remains unclear. The boots were reportedly being manufactured in 1933 by Blue Mountains Ugg Boots of New South Wales. Frank Mortel of Mortels Sheepskin Factory has stated that he began manufacturing the boots in the late 1950s. Surfer Shane Stedman of Australia has stated in interviews that he invented the ugg boot. Perth sheepskin boot manufacturers Bruce and Bronwyn McDougall of Uggs-N-Rugs have manufactured the boots since the late 1970s.