https://www.ibm.com/docs/en/ims/15.6.0?topic=formats-lchild-segment-type-format
IMS 15.6 - Database administration - LCHILD segment type format
The IMS catalog LCHILD segment type contains information about a relationship between segment types.
database administrationsegment typeimsformat
https://manpages.ubuntu.com/manpages/resolute/man3/Child%3A%3AUtil.3pm.html
Ubuntu Manpage: Child::Util - Utility functions for LChild
utility functionsubuntumanpagechild