(20) 
(20.1) NEO-M8 u-blox M8 concurrent GNSS modules Data sheet
https://www.u-blox.com/sites/default/files/NEO-M8-FW3_DataSheet_UBX-15031086.pdf

Abstract - This data sheet describes the NEO-M8 module family which provides concurrent reception of up to 3 GNSS (GPS, Galileo, GLONAS)
(1.6 Assisted GNSS (A-GNSS), Page 8; 1.6.3 AssistNow Autonomous, Page 9)

(20.2) u-blox cellular modules Data and voice modules AT commands manual - u-blox R73 30-Sep-2021 
https://www.u-blox.com/sites/default/files/u-blox-CEL_ATCommands_UBX-13002752.pdf

Abstract - Description of standard and proprietary AT commands used with u-blox
cellular modules. (AT Commands List Page 900)