The materials to the "black book" of the flora of the Crimean Peninsula.

Bagrikova, N. A., Skurlatova, M. V., (2021). Russian Journal of Biological Invasions 12(3), 244-257. Pleiades Publishing, Moscow, Russia. English language

Characteristics of the locality of Opuntia humifusa (Cactaceae) on the territory of the Lozenska Mountain.

Glogov, P., Georgieva, M., Pavlova, D., Dodev, Y., (2020). Nauka za Gorata 56(1), 29-44. Bulgarska Akademiya na Naukite (Bulgarian Academy of Sciences, Central Library), Sofia, Bulgaria. Bulgarian language

Invasion of Opuntia humifusa and O. phaeacantha (Cactaceae) into plant communities of the Karadag Nature Reserve.

Fateryga, V. V., Bagrikova, N. A., (2017). Nature Conservation Research 2(4), 26-39. Fund for Support and Development of Protected Areas, Saransk, Russia. English language

Cactaceae no Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brasil. / Cactaceae in Serra da Tiririca State Park, Rio de Janeiro, Brazil.

Vasconcelos, L. V. F. de, Gonzaga, D. R., Reis, R. C. da C., (2019). Rodriguésia 70 Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio de Janeiro, Brazil. Portuguese language

Opuntia humifusa (Raf.) Raf.: native or naturalized in New Hampshire?

Nichols, W. F., Young, S. A., (2016). Rhodora 118(973), 13-25. New England Botanical Club, Lawrence, USA. English language

The influence of herbivory and weather on the vital rates of two closely related cactus species.

Sauby, K. E., Kilmer, J., Christman, M. C., Holt, R. D., Marsico, T. D., (2017). Ecology and Evolution 7(17), 6996-7009. Wiley, Oxford, UK. English language

Morphological and phytochemical aspects of three alien Opuntia species on Euganean Hills in North-Eastern Italy.

Piovan, A., Caniato, R., Filippini, R., Chiesura, F., Vecchia, F. dalla, (2015). Plant Biosystems 149(4), 788-796. Taylor & Francis, Abingdon, UK. English language

Mixed reproduction systems in Opuntia monacantha (Cactaceae) in Southern Brazil.

Lenzi, M., Orth, A. I., (2012). Brazilian Journal of Botany 35(1), 49-58. Sociedade Botânica de São Paulo, São Paulo, Brazil. English language

Dispersão zoocórica e hidrocórica marítima de Opuntia monacantha (Willd.) Haw. (Cactaceae). / Zoochoric and hydrochoric maritime dispersal of the Opuntia monacantha (Willd.) Haw. (Cactaceae).

Lenzi, M., Graipel, M. E., Matos, J. Z. de, Fraga, A. M., Orth, A. I., (2012). Biotemas 25(1), 47-53. Centro de Ciências Biológicas - UFSC, Santa Catarina, Brazil. Portuguese language

Invasive alien species of vascular plants in Bulgaria.

Vladimirov, V., (2014). Proceedings, 4th ESENIAS Workshop: International Workshop on IAS in Agricultural and Non-Agricultural Areas in ESENIAS Region, Çanakkale, Turkey, 16-17 December 2013, 33. Çanakkale Onsekiz Mart University, Ankara, Turkey. English language