| Kalendarz NASA Ciekawe opracowanie, warte do zawieszenia |
| https://www.nasa.gov/sites/default/files/atoms/files/explore_humans_in_space_on_the_international_space_station_2021_calendar.pdf?fbclid=IwAR3LI_wlJSoRUOG25vVjH0szVcaVnbfBm0Eir1zszLvLpjAKgaIA-jCm4LM |