Hungarian Grey (English Wikipedia)

Charles Darwin (1868). The Variation of Animals and Plants Under Domestication, volume I. London: John Murray.
Ludwig Rütimeyer (1866). Über Art und Raçe des zahmen europäischen Rindes (in German). Braunschweig: [publisher unknown]. Cited in: Charles Darwin (1868). The Variation of Animals and Plants Under Domestication, volume I. London: John Murray.

books.google.com

Marleen Felius (1995). Cattle Breeds: An Encyclopedia. Doetinchem, Netherlands: Misset. ISBN 9789054390176.
Valerie Porter, Lawrence Alderson, Stephen J.G. Hall, D. Phillip Sponenberg (2016). Mason's World Encyclopedia of Livestock Breeds and Breeding (sixth edition). Wallingford: CABI. ISBN 9781780647944.

László Bartosiewicz (1997). The Hungarian Grey cattle: a traditional European breed. Animal Genetic Resources Information (21): 49–60.

Breed data sheet: Magyar Szürke / Hungary (Cattle). Domestic Animal Diversity Information System of the Food and Agriculture Organization of the United Nations. Accessed January 2022.

Marleen Felius, Marie-Louise Beerling, David S. Buchanan, Bert Theunissen, Peter A. Koolmees and Johannes A. Lenstra (2014). On the History of Cattle Genetic Resources. Diversity 6 (4): 705–750. doi:10.3390/d6040705
A. Zsolnai, Á. Maróti-Agóts, A. Kovács, A.V. Bâlteanu, E. Kaltenecker, I. Anton (2020). Genetic position of Hungarian Grey among European cattle and identification of breed-specific markers. Animal. 14 (9): 1786–1792. doi:10.1017/S1751731120000634.
L. Solti, E.G. Crichton, N.M. Loskutoff, S.Cseh (2000). Economical and Ecological Importance of Indigenous Livestock and the Application of Assisted Reproduction to Their Preservation. Theriogenology. 53 (1): 149–62. doi:10.1016/S0093-691X(99)00248-4. (subscription required).

Breed data sheet: Magyar Szürke/Hungary. Domestic Animal Diversity Information System of the Food and Agriculture Organization of the United Nations. Accessed May 2014.

Marleen Felius, Marie-Louise Beerling, David S. Buchanan, Bert Theunissen, Peter A. Koolmees and Johannes A. Lenstra (2014). On the History of Cattle Genetic Resources. Diversity 6 (4): 705–750. doi:10.3390/d6040705

Imre Bodó, István Gera, Gábor Koppány, trans. Béla Borsos (2004). The Hungarian Grey Cattle Breed. Budapest: Magyar Szürke Szarvasmarhát Tenyésztôk Egyesülete.

Barbara Rischkowsky, Dafydd Pilling (editors) (2007). List of breeds documented in the Global Databank for Animal Genetic Resources, annex to The State of the World's Animal Genetic Resources for Food and Agriculture. Rome: Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations. ISBN 9789251057629. Archived 23 June 2020.
Barbara Rischkowsky, Dafydd Pilling (editors) (2007). The State of the World's Animal Genetic Resources for Food and Agriculture. Rome: Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations. ISBN 9789251057629. Archived 10 January 2017.
Mihály Pásztor (editor) (2003). First Country Report on Animal Genetic Resources: Republic 0f Hungary. Budapest: Ministry of Agriculture and Rural Development. Annex to: Barbara Rischkowsky, Dafydd Pilling (editors) (2007). The State of the World's Animal Genetic Resources for Food and Agriculture. Rome: Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations. ISBN 9789251057629. Archived 10 January 2017.
Breed description: Hungarian Grey. Department of Animal Breeding and Genetics, School of Veterinary Medicine Hannover. Archived 15 October 2007.

Anikó Gergely, Ruprecht Stempell, Christoph Büschel, Mo Croasdale (2008). Culinaria Hungary. Potsdam, Germany: H.F. Ullmann. ISBN 9783833149962. OCLC 566879902.