• Current state and historical changes of the ecological status of large lakes Peipsi and Võrtsjärv - running research projects, monitoring and international cooperationNõges, Tiina; Järvet, Arvo; Laugaste, Reet; Loigu, Enn; Nõges, Peeter4th International Lake Ladoga Symposium : Protection and Management of Lake Laadoga and Other Large Lakes : abstracts2002 / p. 12