Simplify the following text for a Grade 10 native English-speaking person.
Original: Other significant publications include the AOU Checklist of North American Birds , which is the standard reference work for the field , and a monograph series , Ornithological Monographs .
Simplified: Some of its other big publications are the AOU Checklist of North American Birds and a series , Ornithological Monographs . The AOU Checklist of North American Birds is the standard reference for the field .