In the Rinshou Hanzaigakusha Himura Hideo no Field Note series:

V.1 - Hitokui no Taki

V.2 - Shuiro no Kenkyuu Yuuhigaoka Satsujinjiken

V.3 - Shuiro no Kenkyuu Karekinan Satsujinjiken

V.4 - 201 Goushitsu no Saiyaku

Note: A reprinted edition was released under the name Russia no Koucha no Nazo.