Edited ch03_bitcoin-core.adoc with Atlas code editor

ch03_bitcoin-core.adoc

@@ -641,7 +641,7 @@ a _README.md_ file showing which system uses ((("Bitcoin Core", "nodes", "config
 === Bitcoin Core API
 
 Bitcoin Core
-implements a JSON-RPC interface that can also be accessed using
+implements((("Bitcoin Core", "command-line interface", id="bitcoin-core-command")))((("command-line interface (Bitcoin Core)", id="command")))((("RPC commands", see="command-line interface (Bitcoin Core)")))((("API", see="command-line interface (Bitcoin Core)"))) a JSON-RPC interface that can also be accessed using
 the command-line helper +bitcoin-cli+. The command line allows us to
 experiment interactively with the capabilities that are also available
 programmatically via the API. To start, invoke the +help+ command to see a list of