Havranek, C. E., & Harris, S. (2020). Butterfly count surveys in field margins at Ditchley Park, Oxfordshire, UK, June - July 2016. University of Oxford.
Chicago-viite (17. p.)Havranek, C E., ja S. Harris. Butterfly Count Surveys in Field Margins at Ditchley Park, Oxfordshire, UK, June - July 2016. University of Oxford, 2020.
MLA-viite (9. p.)Havranek, C E., ja S. Harris. Butterfly Count Surveys in Field Margins at Ditchley Park, Oxfordshire, UK, June - July 2016. University of Oxford, 2020.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.