Connection between the classical ring of quotients of the ring of continuous functions and Riemann integrable functions

The small Fine–Gillman–Lambek extension generated by the classical ring of quotients, and the Riemann extension generated by Riemann $\mu$-integrable functions are both characterized as divisible envelopes of the same type of the ring of all bounded continuous functions on the Aleksandrov space. This shows the similarity of these extensions that are rather different by their origin.