https://www.manualslib.com/manual/72994/Hp-Hp-Procurve-Series-2500.html?page=330

https://www.manualslib.com/manual/858353/Dell-Networking-N4000-Series.html?page=444#manual

https://www.virtualizationhowto.com/2015/09/setup-port-mirroring-dell-nseries-switch/

http://docs.iyunwei.com/docs/network/dell/networking_nxxcli_en-us.pdf

https://niktips.wordpress.com/2016/01/18/beginners-guide-to-dell-n4000-series-switches/

http://wo-net.blogspot.com/2014/10/rspan-on-dell-powerconnect-n-series.html

https://3g-digger.com/articles/302701 - OPS dial numbers

https://red-forum.com/showthread.php?t=14713 - USSD 3Mob

Installing 3G modem

http://raspberry-at-home.com/installing-3g-modem/

https://help.ubuntu.ru/wiki/3g

https://wiki.archlinux.org/index.php/USB_3G_Modem_(%D0%A0%D1%83%D1%81%D1%81%D0%BA%D0%B8%D0%B9)

https://wifi-hotspot.zp.ua/wp/2011/01/ubuntu-3g-modem-terminal/

https://habr.com/ru/sandbox/23113/

https://askubuntu.com/questions/520978/how-to-make-ussd-call-from-huawei-data-card-e1731

https://wammu.eu/gammu/ - утилита командной строки и библиотека для работы с мобильными телефонами различных производителей