Genkosha, a publisher that specializes in illustration and photo books and is based in Tokyo, has released a study book on yuri titled “Yuri no Sekai Nyumon” (aka “The Introduction to the World of Yuri).
Already securing the No. 1 rank in the anime/manga study book category of Amazon Japan, the 128 page book goes over 140 selected titles and series that helped the genre develop and grow.
A feature has Izumi Kitta, a popular seiyuu who voices Cordelia Glauca in the Tantei Opera Milky Holmes series, choosing the eight best yuri manga covers (in her opinion). The book also features interviews with five famous yuri manga-ka: Nio Nakatani (from Yagate Kimi ni Naru / Bloom Into You / Eventually, I Will Become Yours), Canno (from Anoko ni Kiss to Shirayuki wo), Kuzushiro (from Inugami-san to Nekoyama-san), Milk Morinaga (from Girlfriends), and Ken Kurogane (from Shoujo Sect).
You can read more about this magainze here. Sadly, the book itself is all in Japanese. Maybe in the future it’ll get translated.