Juno Mukai Author

(1) Marek Golasinski Institute of Mathematics Casimir the Great University pl. Weyssenhoffa 11 85-07 2 Bydgoszcz, Poland e-mail: [email protected] (2) Juno Mukai Shinshu University Matsumoto, Nagano Pref. 390-8621, Japan e-mail: [email protected]