The object G used in the definition of sums and products of indexed families of cardinals is not described correctly. Currently, the text introduces G, incorrectly, as an element of the Cartesian product of the indexed family F of cardinals. There is an extra parenthesis in the definition of Cartesian products of indexed families of sets, which might be initially confusing. The statement and proof of a theorem is missing here.
Omega is discussed in the next chapter.
This would require that some other definitions be brought forward into this section as well. One could make a remark about the fact that Set Union and Singleton Images together have the effect of enforcing a precise parallelism between structure on objects and structure on their singletons.