Cited in 5 papers to this date: https://scholar.google.com/scholar?hl=de&as_sdt=0%2C5&q=The+validity+and+reliability+of+an+open+source+biosensing+board+to+quantify+heart+rate+variability&btnG= 1. https://www.sciencedirect.com/science/article/pii/S153204642100263X 2. https://www.mdpi.com/2075-1729/12/9/1400 3. https://onlinelibrary.wiley.com/doi/full/10.1002/hsr2.984 4. https://www.sciencedirect.com/science/article/pii/S2665944122000268 5. https://www.frontiersin.org/articles/10.3389/fneur.2022.980938/full The last paper has an impressive list of institutes which are involved Many of those are from the University of Calgary as the validation paper mentioned above about heart rate variablity. https://pubmed.ncbi.nlm.nih.gov/31004219/