Yoshikazu Yasuhiko was tasked as character designer and animation director and story board artist for Fire and Foal (Kaji to Kouma / 火事と小馬) in 1978, which is an informational film about fire safety. The film was produced by CM Movie/Asahi Production and was directed by Kazuhiro Tagaki.
These are the personal xeroxes belonging to my private seller who was kind enough to part with them so that I could scan them in. The xeroxes themselves are very sensitive and otherwise yellowed, but I found ways to clean them up in photoshop to enhance the linework of Yas' art. These are, according to him, not a complete set, but focus on the main characters in the film.
More information from my personal scans: https://twitter.com/retroanimechris/status/1419062646964473858
I do not do this professionally; I am just an avid fan and am sharing what I have with the world the best I can. If you have other materials, please share with everyone. This material is over 40+ years old and we have a brand new generation of people who need to see this history.