Update README.md

Author: witold-swierzy

data-platform/core-converged-db/cross-model-database/README.md

@@ -1,7 +1,11 @@
 # Cross Model Database
 This area focuses on discussing different data models supported by Oracle Converged Database
 
-## Livelabs Workshops  
+# Useful Links
+- [Oracle Database 23c Free - Developer Release Documentation](https://docs.oracle.com/en/database/oracle/oracle-database/23/index.html)
+- [Development with Oracle Converged Database blog post](https://blogs.oracle.com/coretec/post/development-with-converged-database)
+  
+# Livelabs Workshops  
 - [Get Started with Maps and Spatial in APEX](https://apexapps.oracle.com/pls/apex/r/dbpm/livelabs/view-workshop?wid=936&clear=RR,180&session=107096809782354)
 - [Exploring Operational Property Graphs in 23c Free](https://apexapps.oracle.com/pls/apex/r/dbpm/livelabs/view-workshop?wid=3659&clear=RR,180&session=107096809782354)
 - [Get started with Converged Database for Developers - On Premises](https://apexapps.oracle.com/pls/apex/r/dbpm/livelabs/view-workshop?wid=613&clear=RR,180&session=107096809782354)