* 636.1: This covers horses and related animals like donkeys, mules, and zebras. This section includes topics like breeding, care, and diseases.
* 798.2: This covers horse sports and racing, including equestrian events like jumping and dressage.
* 599.73: This covers mammals, including the biological aspects of horses.
* 970.1: This covers Native American cultures, and might include information about the role of horses in Native American life.
To find books about horses, you'll need to search for specific topics under these broader categories, depending on what you're looking for. For example, to find books on horse care, you would look under 636.1, while to find books on horse racing, you would look under 798.2.