Deliverables
Communicating the User Experience: A practical guide for creating useful UX documentation.
Caddick, R., Cable, S.
Design Systems. (Smashing Ebooks)
Kholmatova, A.
Front-end style guides.
Debenham, A.
Interaction Design

Interaction Design: beyond human-computer interaction
Yvonne Rogers, Helen Sharp, Jenny Preece
A very complete book about interaction design. It explains interaction design providing numerous examples, resources and references. Also you can find numerous practical cases all along the book so you can apply the theory.
Psychology

100 Things every designer needs to know about people
Susan Weinschenk
In this book, Susan gives us a hint on how our brain works and why we do things the way we do. With very illustrative examples and lots of references to psycology researches to dig deeper in the subject. Though we can consider this book as a basic for any UX designer and UX developer we can say it is also a must-have in your bookshelf, as it counts with a very dense bibliography
Creativity. Flow and the psychology of discovery and invention.
Mihaly Csikszenmihalyi
Sensation and Perception
Bruce Goldstein, Colin Ryan and John Baro
Workshops & Methodology

Lean UX: applying agile principles to improve User Experience
Jeff Gothelf with Josh Seiden
How to Run a Great Workshop
Nikki Highmore Sims
Reference Books

Designing interfaces: Patterns for effective interaction Design
Jenifer Tidwell
When I first discovered the web site ten years ago I found it very useful for my final project disertation and in general for work. It describes in depth UI patterns and solutions as well as UI best practices by giving numerous examples on how to apply them and providing online resources
I have been using this book for many years as a reference and every time I find a new problem I go back to my UX bookshelf to use it as an starting point in the research on how to solve it.

Universal Principles of Design: 125 Ways to Enhance Usability, Influence Perception, Increase Appeal, Make Better Design Decisions and Teach through Desing
William Lidwell, Kritina Holden, Jill Butler
As mentioned in Interaction desing: beyond human-computer interaction one inspiration resource for creating good principles when evaluating a prototype or an interface is using design principles. This is a good book to start with. As mentioned in the introduction desing is affected by principles coming from different disciplines as it happens in HCI. Using this exhaustive list can be very useful when evaluating and developing a system.

Undercover User Experience Design
Cennyd Bowles and James Box
I discovered this book just recently in an UX bootcamp organized by GA. I find it very useful to get an overview of the UX processes in all stages of the design process as well as a good reference book for resources and techniques.
It also provides tips to introduce UX processes in agile environments and start-ups that lacks a team dedicated to UX design.
Usability
The design of every day things
Donald A. Norman
Designing Usability.
Nielsen, J.
Prioritizing Web Usability
Nielsen, J. and Loranger, H.
Software for Use. A practical guide to the model and methods of Usage Centered Design.
Constantine and Lockwood
Usability. The site speaks for itself.
Braun, K., Gadney, M. and 5 more.
Innovative Techniques of web design.
Penny McIntire
Information Architecture
Information Architecture
Rosenfel, L., Morville, P., Arango, J.