Hard-photon production at root s=161 and 172 GeV at LEP by Acciarri, M, Adriani, O, AguilarBenitez, M, Ahlen, S, Alcaraz, J, Alemanni, G, Allaby, J, Aloisio, A, Alverson, G, Alviggi, MG, Ambrosi, G, Anderhub, H, Andreev, V, Angelescu, T, Anselmo, F, Arefiev, A, Azemoon, T, Aziz, T, Bagnaia, P, Baksay, L, Banerjee, S, Banerjee, S, Banicz, K, Barcyzk, A, Barillere, R