LibreCat/Catmandu-MARC — pull request #3 by eythian (2014-03-03 06:30:50+00:00)
Title: Allow the MARC field that the _id comes from to be a subfield

An _id can be sourced from a control field, or from NNN subfield a. This
allows the id parameter provided to be in the form NNNb, where it will
get the ID from subfield b of field NNN.