https://animalogic.ca/blog/everything-you-ever-wanted-to-know-about-the-common-swift

https://www.zentrumfuercitizenscience.at/en/p/mauersegler-in-wien

https://www.hbw.com/ibc/photo/common-swift-apus-apus/juvenile-common-swift-or-different-individuals-were-seen-bom-bom

https://peakboxes.co.uk/knowledge-learning-blog/swiftfolklore

https://www.britishbirdlovers.co.uk/bird-brain/is-it-true-swifts-cant-take-off-from-the-ground

http://news.bbc.co.uk/earth/hi/earth_news/newsid_8539000/8539383.stm

https://www.flickr.com/photos/knaton/9100693654/

https://news.cision.com/lunds-universitet/i/common-swift,c2000703

http://birdsofeurope.eu/birds.php?l=en&cat=11&sub=34&vid=225&type=bird