No 40 VI‐2020

https://www.youtube.com/watch?v=SGRnKP9B1ho&t=47shttps://www.youtube.com/watch?v=U5xU9SCp4ng&t=6shttps://youtu.be/skH_wpE9900https://youtu.be/-3lmyj5Ljbwhttps://youtu.be/O6pPTdypv8A

http://sac.csic.es/unawe/cuentos/tierra.pdfhttps://www.apea.es/wp-content/uploads/28-El-Globo-Terr%C3%A1queo-una-Bola-casi-M%C3%A1gica.pdf

http://www.astroosona.net/web/Apunts/Equaci%F3%20del%20temps%20i%20analemes.pdf

http://www.naseprogram.org