Professor Risto Tuomikoski Memorial Issue

Including articles: Timo Koponen, The biography of Professor Risto Tuomikoski: bryologist, entomologist, linguist, mycologist, vegetation scientist and ecologist; Rauno Ruuhijärvi, Risto Tuomikoski as a vegetation researcher and ecologist; Timo Koponen, Risto Tuomikoski as a bryologist; Veikko Hintikka, Risto Tuomikoski as a mycologist; Pekka Vilkamaa, Risto Tuomikoski as an entomologist; The Tuomikoski letters.