1. Bertelli, A., Biachi, C., Baeni, L.: Interaction between beta-adrenergic stimulant and phosphodliesterase inhibiting drugs on the bronchial muscle. Experientia 29, 300 (1973).
2. Campell, I. A.: Interaction between salmefamol and choline theophyllinate/theophylline in asthma. Brit. J. Dis. Chest 70, 276 (1976).
3. Campbell, I. A., Middleton, W. G., McHardy, G. J. R., Shotter, M. V., McKenzie, K., Kay A. BB.: Interaction between isoprenaline and aminophylline in asthma. Thorax 32, 424 (1977).
4. Chick, T. W., Jenne, J. W., Strickland, R. D., Wall, F. J.: A single oral dose comparison or aminophylline and terbutaline, separately and in combination. Amer. Rev. Resp. Dis. 113, 165 (1976).
5. Dyson, A. J., Campbell, I. A.: Interaction between choline theophyllinate and salmetamol in patients with reversible airways obstruction. Brit. J. Clin. Pharmacol. 4, 677 (1977).