ERROR IN DEMARTRES'S PAPER AND THE CORRECT RESULT
SIMULTANEOUS APPROXIMATION BY MODIFIED BETA OPERATORS
THE 2'-R GROUPS WITH ONE CONJUGACY CLASS OF INVOLUTIONS
AMBIVALENT GROUPS HAVING STRONGLY EMBEDDED SUBGRUOPS
ABOUT A CONJECTURE OF DEACONESCU
THE SOLVABLE Q-GROUPS WITH ONE CONJUGACY CLASS OF INVOLUTIONS
2'-R GROUPS HAVING A FAITHFUL MONOMIAL IRREDUCIBLE CHARACTER