Ndayirukiye, A., Ndikuryayo, F., Mpawenayo, P. C., Ngezahayo, J. and Gahungu, G. (2026) “Theophylline and Caffeine Content in Black Tea Produced in Burundi”, European Scientific Journal, ESJ, 490, p. 600. Available at: https://eujournal.org/index.php/esj/article/view/20572 (Accessed: 25January2026).