This is my YANG doctor review of draft-ietf-babel-yang-model containing ietf-babel@2021-03-12.yang module. The draft and the module are well written and I have just two minor comments:

- The copyright year in the YANG module should be probably 2021, not 2020.

- Some values of the specific statements (e.g. min-elements) are quoted despite it is not necessary (the value must be a number or a single word). I propose to use pyang/yanglint to generate the module since it also unifies all the formatting and quoting.