Gupta S, George P, Gupta V. Tylophora indica in bronchial asthma: A double-blind study. Indian J Med Res, v.69, 981-989. 1979.
Shivpuri DN, Menon MP, Prakash D. A crossover double-blind study on Tylophora indica in the treatment of asthma and allergic rhinitis. J Allergy, v.43, 145-150. 1969.
Shivpuri DN, Singhal SC, Parkash D.Treatment of asthma with an alcoholic extract of tylophora indica: A cross-over, double-blind study. Ann Allergy, v.30, 407-412. 1972.
Mathew KK, Shivpuri DN. Treatment of asthma with alkaloids of Tylophora indica: A double-blind study. Aspects Allergy Appl Immuno, v.7, 166-179. 1974.
Thiruvengadam KV, Haranath K, Sudarsan S. Tylophora indica in bronchial asthma: A controlled comparison with a standard anti-asthmatic drug. J Indian Med Assoc, v.71, 172-176. 1978.
Wen MC, Wei CH, Hu ZQ, Srivastava K, Ko J, Xi ST, Mu DZ, Du JB, Li GH, Wallenstein S, Sampson H, Kattan M, Li XM. Efficacy and tolerability of anti-asthma herbal medicine intervention in adult patients with moderate-severe allergic asthma. J Allergy & Clinical Immunology, 116(3):517-24, Sept. 2005.
Gupta I, Gupta V, Parihar A, Gupta S, Ludtke R, Safayhi H, Ammon HP. Effects of Boswellia serrata gum resin in patients with bronchial asthma: Results of a double-blind, placebo-controlled, six-week clinical study. European Journal of Medical Research, 3(11):511-4. Nov. 1998.