In the preface of "Stages to Saturn", the author Robert E. Bilstein writes:
This book is a technological history. [...] Two other histories, already published, deal with subjects keyed to the Apollo Saturn Program: (1) the development of the Apollo command and service modules along with the lunar module and (2) the construction and operation of launch facilities at Cape Kennedy.
What are the two books he is referring to?
Stages to Saturn NASA SP-4206 (1979) By Robert E. Bilstein (web version) (pdf version)