diff --git a/citations.txt b/citations.txt
index ef58a09..f73a9d5 100644
--- a/citations.txt
+++ b/citations.txt
@@ -40,6 +40,8 @@ DeepFace is cited by the following papers.
 
 [14] Yalavarthi Bharat Chandra et al, A Comparative Analysis Of Face Recognition Models On Masked Faces, International Journal of Scientific & Technology Research. Vol 9, Issue 10. 2020.
 
+[15] Pelkonen, Riku. "Holmes–virtuaalinen ovimies." (2021).
+
 Based on the following academic repositories
 
 [1] Google Scholar: https://scholar.google.com/scholar?oi=bibs&hl=tr&cites=17652496388087594988