Add requested sections of handover procedures

Author: b-branco

articles/private-5g-core/statement-of-compliance.md

@@ -22,12 +22,15 @@ All packet core network functions are compliant with Release 15 of the 3GPP spec
 
 - TS 23.003: Numbering, addressing and identification.
 - TS 23.501: System architecture for the 5G System (5GS).
-- TS 23.502: Procedures for the 5G System (5GS).
+- TS 23.502: Procedures for the 5G System (5GS). Includes the sections:
+  - 4.9.1.2: Xn based inter NG-RAN handover.
+  - 4.9.1.3: Inter NG-RAN node N2 based handover.
 
 ### 4G system
 
 - TS 23.002: Network architecture.
-- TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access.
+- TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access. Includes the section:
+  - 5.5.1.1 X2-based handover.
 - TS 29.272: Evolved Packet System (EPS); Mobility Management Entity (MME) and Serving GPRS Support Node (SGSN) related interfaces based on Diameter protocol.
 - TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS) Tunneling Protocol for Control plane (GTPv2-C); Stage 3.
 - TS 33.401: 3GPP System Architecture Evolution (SAE); Security architecture.