elkai-rs
  by HellOwhatAs
Due to the elkai restrictions, elkai-rs is solely available
for academic and non-commercial use and distribution.
The Rust code and all wrapper code is free open
source software: https://www.rust-lang.org/policies/licenses

elkai (https://github.com/fikisipi/elkai)
  by Filip Dimitrovski
Due to the LKH restrictions, elkai is solely available
for academic and non-commercial use and distribution.
The CPython code and all wrapper code is free open
source software: https://docs.python.org/3/license.html

LKH (http://akira.ruc.dk/~keld/research/LKH/)
  by Keld Helsgaun
The code is distributed for academic and non-commercial use.
The author reserves all rights to the code.