Need help identifying the artist or the source of this anatomy study

\"Unknown Artist\"

Hi everyone! I found this figure drawing study and I'm trying to find the original artist or the instructional course it belongs to. It looks like a "structural/constructive" anatomy sketch (similar to Steve Huston or Glenn Vilppu style). The model has a distinct athletic build and is sitting on a stool. Does anyone recognize this from a specific art book, Patreon, or online course (like New Masters Academy or Proko)? Any leads would be appreciated!