Refer to the following references to read more

1. "Unity Virtual Reality Projects: Learn Virtual Reality by Developing More than 10 Engaging Projects with Unity 2018" by Jonathan Linowes and Krystian Babilinski.
2. "Unreal Engine Virtual Reality Quick Start Guide: Design and Develop Immersive Virtual Reality Experiences with Unreal Engine 4" by Jessica Plowman.
3. "Unity Virtual Reality Development: A Beginner's Guide to Developing Immersive Virtual Reality Experiences with Unity" by Jonathan Linowes.
4. "Mastering Unreal Engine 4.X: A comprehensive guide to developing stunning games with Unreal Engine 4" by Satheesh PV.
5. "Unreal Engine 4 Virtual Reality Projects: Build immersive, real-world VR applications using UE4, C++, and Unreal Blueprints" by Kevin Mack.