Sommaire

Periodic traveling waves in the system of linearly coupled nonlinear oscillators on 2D-lattice
p. 1-13
Cyclic congruences of slim semimodular lattices and non-finite axiomatizability of some finite structures
p. 15-33
The Ribes-Zalesskii property of some one relator groups
p. 35-47
A half-space type property in the Euclidean sphere
p. 49-63