BT. van den Berg, RT. Louwerse; GJ. Luiken; RE. Jonkers; CJ. van Boxtel, Hypokalaemia in healthy volunteers after single and multiple doses of formoterol or salbutamol., in Clin Drug Investig, vol. 15, n. 6, 1998, pp. 523-9, PMID18370510.
R. Sannerstedt, P. Lundborg; BR. Danielsson; I. Kihlström; G. Alván; B. Prame; E. Ridley, Drugs during pregnancy: an issue of risk classification and information to prescribers., in Drug Saf, vol. 14, n. 2, Feb 1996, pp. 69-77, PMID8852521.