- 2018 Walkers Mammals
- Squirrels of the world
- Kays & Wilson North American mammal guide
- China mammal guide
- Mammals of Mexico
- Various other general wildlife guides or local mammal guides.
A number of US academic publishers are making books available for free download during Covid 19, via the Project Muse website. This includes a number of recent mammal books. Try this link, or if it doesn’t work for you go to the Project Muse website, search for mammals and then filter for things you have access to.
Books available include:
The only downside is you have to download chapter by chapter. But it’s easy enough to merge them afterwards. I am using free software called PDFsam Merge.