| https://www.cosmos.esa.int/web/xmm-newton |
| http://heasarc.gsfc.nasa.gov/docs/xmm/xmmgof.html |
| http://xmmssc.irap.omp.eu/ |
| https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk |
| xmmhelp@athena.nasa.gov |
| https://www.cosmos.esa.int/web/xmm-newton/observation-log-browser |
| http://heasarc.gsfc.nasa.gov/db-perl/W3Browse/w3browse.pl |
| https://www.cosmos.esa.int/web/xmm-newton/short-term-schedule |
| https://www.cosmos.esa.int/web/xmm-newton/xsa
|
| http://heasarc.gsfc.nasa.gov/db-perl/W3Browse/w3browse.pl |
| https://www.cosmos.esa.int/web/xmm-newton/calibration |
| https://heasarc.gsfc.nasa.gov/FTP/caldb/data/xmm/ |
| https://www.cosmos.esa.int/web/xmm-newton/sas |
| https://heasarc.gsfc.nasa.gov/docs/xmm/esas/cookbook/xmm-esas.html |
| https://heasarc.gsfc.nasa.gov/docs/corp/software.html |
| https://asc.harvard.edu/ciao/ |
| https://xmm-tools.cosmos.esa.int/external/xmm_user_support/documentation/sas_usg/USG/ |
| https://www.cosmos.esa.int/web/xmm-newton/sas-watchout |
| https://www.cosmos.esa.int/web/xmm-newton/sas-threads |
| https://xmm-tools.cosmos.esa.int/external/sas/current/doc/packagelist.html |
| https://xmm-tools.cosmos.esa.int/external/xmm_user_support/documentation/uhb/index.html |
| https://heasarc.gsfc.nasa.gov/docs/xmm/abc/ |