[iOS] Core Data references

Getting Started with Core Data
Introduction to Core Data Programming Guide
Core Data Tutorial for iOS
Introduction to Core Data Utility Tutorial
XCode Entity Modeling Tools for Core Data
XCode Mapping Tool for Core Data
Core Data Model Versioning and Data Migration
Core Data Release Notes for iOS v5.0
Using Core Data with iCloud Release Notes

Sample Code:
Top Songs
iPhoneCoreDataRecipes
ThreadedCoreData
PhotoLocations
TaggedLocations
Locations
CoreDataBooks
DateSectionTitles

Reference:
Core Data Framework Reference