TY - JOUR AU - PAPACHRISTODOULOS, CHRISTOS TI - UPPER AND LOWER FREQUENTLY UNIVERSAL SERIES JO - Glasgow mathematical journal PY - 2013 SP - 615 EP - 627 VL - 55 IS - 3 UR - http://geodesic.mathdoc.fr/articles/10.1017/S001708951200078X/ DO - 10.1017/S001708951200078X ID - 10_1017_S001708951200078X ER -