3GPP 23.501 v20.2.0 — the document's own text

5.40.7.1 General

Taught in 27. Overload, energy, deployment and the rest (The 5G system architecture, in depth).

The UE can obtain Disaster Roaming service in EPS as described in clause 4.14 of TS 23.401 [26]. This clause describes additional aspects which has to be supported in 5GS procedures to provision the configurations required to support Disaster Roaming service in EPS.