The "Apple IIc Technical Reference Manual, Second Edition" from Apple Computer is available from APDA. This publication includes sections specific to the Apple IIc Plus, unlike the original Addison-Wesley edition.
The part number is A2G0052/A; the "/A" indicates the second edition. For more details, search the Technical Info library under "APDA."
We don't know of any other technical publications specifically for the Apple IIc Plus.
The Tech Info Library Article 17159: "
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