Optical and radio variability of the BL Lacertae object AO 0235+16: A possible 5-6 year periodicity

RAITERI C.M; VILLATA M; ALLER H.D; ALLER M.F; HEIDT J; KURTANIDZE O.M; LANTERI L; MAESANO M; MASSARO E; MONTAGNI F; NESCI R; NILSSON K; NIKOLASHVILI M.G; NURMI P; L. OSTORERO; PURSIMO T; REKOLA R; SILLANPAEAE A; TAKALO L.O; TERAESRANTA H; TOSTI G; BALONEK T.J; FELDT M; HEINES A; HEISLER C; HU J; KIDGER M; MATTOX J.R; MCGRATH E.J; PATI A; ROBB R; SADUN A.C; SHASTRI P; WAGNER; S.J; WEI J; WU X