%% You should probably cite rfc9545 instead of this I-D.
@techreport{ietf-spring-mpls-path-segment-01,
    number =    {draft-ietf-spring-mpls-path-segment-01},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-spring-mpls-path-segment/01/},
    author =    {Weiqiang Cheng and Han Li and Mach Chen and Rakesh Gandhi and Royi Zigler},
    title =     {{Path Segment in MPLS Based Segment Routing Network}},
    pagetotal = 11,
    year =      2019,
    month =     sep,
    day =       16,
    abstract =  {A Segment Routing (SR) path is identified by an SR segment list. Only the full segment list identifies the full end-to-end path, and one segment or a partial set of segments from the list cannot identify the SR path and distinguish it from other SR paths that may be partially congruent. But path identification is a pre-requisite for various use-cases such as performance measurement (PM) of an SR path. In SR for MPLS (SR-MPLS) the segment identifiers are stripped from the packet through label popping as the packet transits the network. This means that when a packet reaches the egress of the SR path, it is not possible to determine on which SR path it traversed the network. This document defines a new type of segment that is referred to as Path Segment, which is used to identify an SR path in an SR-MPLS network. When used, it is inserted at the ingress node of the SR path and immediately follows the last segment identifier in the segment list of the SR path. The Path Segment will not be popped off until it reaches the egress node of the SR path. A Path Segment can be used by the egress node to implement path identification hence to support various use-cases including SR path PM, end-to-end 1+1 SR path protection, and bidirectional SR paths correlation.},
}