There are several cat breeds with folded or curled ears. They are popular for their distinctive appearance and charming personalities. The Scottish Fold is the most popular of curled-ear kitties.
American Curl Cats: Small Ears, Big Personality
American Curl – cat with unusual ears
The American Curl cat – Cat in the Box LLC
13 Rare Cat Breeds That Make Extra-Special Companions, cats breeds
Scottish Fold (Highland Fold) Cat Breed Information & Characteristics
5 Things You Didn't Know About Scottish Fold Cats
Scottish Fold Facts - Wisdom Panel™ Cat Breeds
10 Unique Cat Breeds: Most Unusual-Looking Cats
5 Strange and Interesting Cat Breeds - PetHelpful
Odin's New Cauliflower Ears: Feline Auricular Hematoma