"The Forever War" was my first introduction to this form of time stretching. I actively search out authors who incorporate it into their storytelling, so I was thrilled when I stumbled across Alastair Reynolds' writing.

I think I have all of his books now.

Vinge's "A Deepness in the Sky".

I believe Larry Niven had one as well; I don't remember how long it lasted, due to relativistic effects.

The Ethics of Madness, I think it was called.

I think it lasted indefinitely. Both people had life-extension technology on their ships and they were Bussard ramjets of the "can accelerate forever" variety.

Another classic relativistic story is Pohl's _Starburst_.

House of Suns generally seemed to make me viscerally feel Deep Time. I was rather impressed with that aspect in particular.

I recommend Permutation City. https://www.amazon.com/Permutation-City-Greg-Egan-ebook/dp/B...