University Physics, 14th Edition, Young And Freedman, Addison Wesley, 2015.

It's easy to write correct Ruby code, but to gain the fluency needed to write great Ruby code, you must go beyond syntax and absorb the "Ruby way" of thinking and problem solving.

The Go-To Resource for Large-Scale Organizations to Be Agile
Rather than asking, “How can we do agile at scale in our big complex organization?” a different and deeper question is, “How can we have the same simple structure that Scrum offers for the organization, and be agile at scale rather than do agile?” This profound insight is at the heart of LeSS (Large-Scale Scrum).

Develops precise statements about performance, supported by appropriate mathematical models and empirical studies validating those models.