Increased Urinary Excretion of 3-methoxytyramine in Patients with Head and Neck Paragangliomas - van Duinen, N; Steenvoorden, D; Kema, I P; Jansen, J C; Vriends, A H; Bayley, J P; Smit, J W; Romijn, J A; Corssmit, E P (J Clin Endocrinol Metab, 2010)