Articels:

https://www.sciencedaily.com/releases/2012/06/120622163056.htm

https://www.urbanwildlifesociety.org/pigeons/pijvalu.html

https://www.wildscapingworldwide.com

https://tootool.co/en-us/Products/6/pigeon/10/manure

https://theculturetrip.com

https://www.discoverwildlife.com/animal-facts/birds/feral-pigeon-flying-rat-or-urban-hero

https://en.wikipedia.org/wiki/War_pigeon

https://healthypigeons.yolasite.com

https://www.humanesociety.org/resources/what-do-about-pigeons

https://bklyner.com/in-defense-of-pigeons-bensonhurst

https://www.pigeoncontrolresourcecentre.org/html/amazing-pigeon-facts.html

https://www.pigeoncontrolresourcecentre.org/html/cleaning-pigeon-droppings.html

https://journeyintodreams.com/dove-symbolism-pigeon-meaning

https://www.birdcontrolsolutions.net

https://www.pestsmart.org.au

www.picasuk.com

https://pigeonpedia.com/pigeon-birth-control/

https://www.flowerpower.com.au/garden-advice/gardening/bird-attracting-plants

https://www.erna-graff-stiftung.de/

https://www.downwell.co.uk/pigeon-guano-removal-services/

https://www.cdc.gov/

https://www.standardpest.com/

https://www.birdsandgeesebeware.com/

https://www.psychologytoday.com/intl/blog/the-asymmetric-brain/201907/the-surprising-neuroscience-pigeon-intelligence

https://www.psychologytoday.com/intl/blog/the-mind-menagerie/202007/keeping-pigeons-close-our-hearts

https://www.notechmagazine.com/2016/10/pigeon-towers-a-low-tech-alternative-to-synthetic-fertilizers.html

https://www.awm.gov.au/articles/blog/pigeons-at-war?fbclid=IwAR1pMdeR7Hg2UEu02HL9BjGbh-e_XYLuC8f8iMVjui3ktf3t_HV8tslb15k

https://www.unilad.co.uk/animals/pigeon-who-used-poppies-to-make-nest-welcomes-baby-at-war-memorial/

http://bird.lu/

Regulation of the street pigeon in Basel by Daniel Haag-Wackernagel, 1992

Photos:

https://www.pinterest.com

https://www.deviantart.com

https://www.flickr.com

https://www.pikist.com

https://www.facebook.com/Joel2020

https://www.facebook.com/gina.jockwer

https://www.facebook.com/guiza.christiane

https://www.instagram.com/thepigeonphotographer

https://www.instagram.com/pigeon.story

https://www.instagram.com/pigeons_of_wurzi

https://dreamastromeanings.com/spiritual-meaning-of-white-dove-flying-in-front-of-you

https://eco-villages.eu/en/2019/12

https://brewminate.com/a-history-of-pigeon-post-since…

https://stackward.com/17-proofs-that-pigeons-totally-know-how-to-read/5622

https://fotovmire.ru/foto-golubej.html

https://www.twpinc.com/wire-mesh-material

https://en.imna.ir/news/387603/Pigeon-Towers-Masterpieces-of-Persian-Architecture