Air-breathing rocket engines: the future of space flight – Physics World
The Rocket Motor of the Future Breathes Air Like a Jet Engine | WIRED
The Efficient Future of Deep-Space Travel--Electric Rockets - Scientific American
ISRO upcoming engine sce-200 will power their future rocket and reusable vehicles. (similar in strength to raptor and uses a Oxygen rich closed cycle and kerelox) : r/space
Inside the Rocket Engine Powering the Future of Space Exploration
What are the most likely forms of space propulsion in the future? - Quora
Incredible Technology: Superfast Trips to Mars | Space
Spacecraft propulsion - Wikipedia
Next-Gen Propulsion System Gets $67 Million from NASA | Space
To The Moon And Back, Aerojet Wants To Power Future Cislunar Economy | Aviation Week Network
Why the Aerospike Engine Is the Future of Rockets and Spaceflight