Sommaire du Fascicule no. 1
p. 49-62
Sommaire du Fascicule no. 3
p. 319-328
p. 347-363
On the connection between spectral and oscillation properties of the Sturm--Liouville matrix problem
p. 365-378
Sommaire du Fascicule no. 4
p. 425-443
p. 479-491