by Lehtonen, Keijo, Hänninen, Kari, Ketola, Martti
Published in Organic geochemistry (01.01.2001)

by Lehtonen, Keijo, Ketola, Martti
Published in Organic geochemistry (1990)

by Lehtonen, Keijo, Ketola, Martti
Published in Organic geochemistry (1993)

by Lehtonen, K, Ketola, M, Pihlaja, K
Published in International journal of environmental analytical chemistry (01.03.1991)

by Ketola, Martti, Luomala, Erkki, Pihlaja, Kalevi, Nyrönen, Timo
Published in Fuel (Guildford) (01.05.1987)

by Lehtonen, K, Ketola, M, Haihu, K, Pihlaja, K
Published in Suo (1988)