Just do them yourself. The person who used that is using Loomis as a reference.
You should really be studying from real life to be honest.
But, you don't need stuff like that. You just need to learn anatomy by studying Paul Richer or Loomis.
If you want to be able to build the base mesh for that, you can look at this https://www.youtube.com/watch?v=spi4lGxnMZg
If you search turnaround you can find a ton of what you are looking for. But, I would learn proper anatomy before stylization.