Inside Interesting Integrals - Paul J. Nahin (Springer, 2015)

If you want to improve your integration skills this is the book for you.  The perfect book if you are stuck at home on a snow day and you like to make calculations (I am, and I do.)  My only quibble with this book is that the author uses MATLAB to check his results.  I prefer books that teach students to determine whether the answers make sense.  I suppose that most people use numerical routines to check results these days - but keep in mind that they don't always get the right answer.  Personally, I'd prefer to use Python or R to check the results - I prefer that students know what algorithms are being used.  All in all,   a worthwhile book.

Doing Bayesian Data Analysis - John K. Krushke (Academic Press, 2015)

I have been interested in Bayesian methods for many years - this book makes the calculations accessible to almost anyone.  The current version of the book is the second editions, it was published in 2015.  For an overview, I suggest visiting the author's webpage.  Simply the book explains how to implement Bayesian methods.  As well as providing an overview of Bayesian methods, the book provides and introduction to the appropriate software tools: R, JAGS, and Stan.

An Introduction to the Theory of Infinite Series - T.J.I'A. Bromwich

If you own only one book on infinite series, this is the book to own.  My copy is a second edition, first printed in 1928 by MacMillan - my copy is from 1949.  It has been reprinted by MacMillan and others since.  It's an easy read if you are familiar with Hardy's Pure Mathematics or other books at a similar level.  Coverage includes sequence, real, and complex series, power series and gamma functions.  The book contains an illuminating discussion of uniform convergence.  If you use series in your work as a mathematician or a physicist, this book should be on your bookshelf.