Quectel, GSM/GPRS Modules, models:

5G-M2 EVB	User Manual
AF20	Hardware Design
BC65-TE-B	User Manual
BC66	Hardware Design
BC68	Manual
BG95 Series	Hardware Design
BG950A-GL	Manual
BG96	Application Note
EC21 Mini PCIe Series	Hardware Design
EG12 Series	Hardware Design
EG21-G	Hardware Design Reference Design
EG25-GL	Hardware Design
FC41D-TE-B	User Manual
FC800L	Manual
GL100	Manual
GSM QuecCell	Command Manual
GSM/GPRS Module Series	Command Manual
HSPA+ Series	Hardware Design
L89 R2.0	User Manual
LC79D (A) EVB	User Manual
M10	Hardware Design
M20	Hardware Design
MC60	Reference Design
Mini PCIe-C EVB	User Manual
RM505Q-AE	Manual
RMU500-EKNM	User Manual
SC200E Series	Manual
UC20	At Command Manual
UMTS Module Series	Hardware Design
UMTS<E EVB R2.0	User Manual