I am interested in a good comprehensive resource on realification and complexification of vector spaces over the reals or complexes (and the interplay of these structures on the 'same' space in general).
In particular, understanding of the basic theory is necessary and useful for a more intuitive approach towards functional analysis.
Can you give me a tip? For example, Serge Lang's classical book does not explicitly work this part out. I am aware of a few pages in Arnold's book on ODE, but there should be something more comprehensive and neat somewhere out there.