Paper  bibtex   

@misc{Calliope-Hacksterio-Heartrate,
	author = {Sven Haiges},
	copyright = {CC BY},
	date = {2017-02-20},
	keywords = {Calliope-Code},
	note = {L\"{a}sst den Puls messen und ben\"{o}tigt daf\"{u}r zus\"{a}tzliche Hardware im Wert von 13,95 Euro.},
	title = {{Calliope Heart Rate Sensor}},
	annote = {https://www.hackster.io/hansamann/calliope-heart-rate-sensor-82cc92},
	url = {https://is.gd/0IfcEv},
	urldate = {2017-05-18}
}