TS 102 361-1.pdf - Official DMR Specification. Document 1 of 4 - DMR Air Interface (AI) protocol
TS 102 361-2.pdf - Official DMR Specification. Document 2 of 4 - DMR voice and generic services and facilities
TS 102 361-3.pdf - Official DMR Specification. Document 3 of 4 - DMR data protocol
TS 102 361-4.pdf - Official DMR Specification. Document 4 of 4 - DMR trunking protocol
ETSI TR 102 398.pdf -  Digital Mobile Radio (DMR) General System Design