About Horst Krause Books by Horst Krause Rocky Mountain Animal Tracks by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause Ontario Animal Tracks by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause Northern California Animal Tracks by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause Washington and Oregon Animal Tracks by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause Animal Tracks of Arizona & New Mexico by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause Animal Tracks of the Great Lakes by (author) Ian Sheldon illustrated by Gary Ross & Horst Krause