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I have two essential books:

1) https://www.amazon.com/Baby-Whisperer-Solves-Your-Problems/d...

Good sleep habits should be the #1 priority with a newborn (to the extent you can do anything about it).

2) Peaceful Parents Happy Kids https://www.ahaparenting.com

When kids get older (toddler and up) this book is very evidence based, and is very helpful for dealing with relationship conflicts.