Petkova-Gueorguieva, E., Gueorguiev, S., Lebanova, H., Madzharov, V., & Mihaylova, A. Survey on Sildenafil, Tadalafil, and Vardenafil Concentrations in Food Supplements for Erectile Dysfunction. Wiley.
Chicago Style (17th ed.) CitationPetkova-Gueorguieva, Elina, Stanislav Gueorguiev, Hristina Lebanova, Vasil Madzharov, and Anna Mihaylova. Survey on Sildenafil, Tadalafil, and Vardenafil Concentrations in Food Supplements for Erectile Dysfunction. Wiley.
MLA (9th ed.) CitationPetkova-Gueorguieva, Elina, et al. Survey on Sildenafil, Tadalafil, and Vardenafil Concentrations in Food Supplements for Erectile Dysfunction. Wiley.
Warning: These citations may not always be 100% accurate.