The OKBC Specification is hard to read. Any helpful hints ?
This depends for which purpose you have to use the OKBC specification.
For your first reading, read Chapter 1, 2, Sections 3.1-3.5 and Chapter 4. Before a detailed reading of Chapter 3, it is best to have read the Chapter 4.
For an implementation-oriented reader, while reading Section 3.5, reading the source code for the default implementation of OKBC operations (in files core*.lisp) can be useful.
Next: Do you have some references for background
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