“…In this line of argument, the HTB condition is crucial. It is worth noting that, for maps between certain domains in
, η‐quasisymmetry can be derived from H ‐quasisymmetry without the HTB property (see [
6, 17]). However, the proofs in [
6, 17] used some special properties and modulus estimates in the Euclidean space that may not be true in general metric spaces.…”