The Book Of Many Cross-References

In recent posts, discussion of Poul Anderson's The Boat Of A Million Years has involved reference to his:

Time Patrol Series;
The King Of Ys (with Karen Anderson);
Tales Of The Flying Mountains;
"Flight to Forever";
Orion Shall Rise;
Brain Wave;
World Without Stars
Dominic Flandry series;
Starfarers;
other "STL future histories";
by implication, one short story about a stranded time traveler and another about a stranded extraterrestrial.

Since I have as yet reread only as far as Chapter IV, section 3 (of 16), other cross-references may become relevant. So far, each chapter has introduced an immortal:

I, Thule - Hanno in 310 BC;
II, The Peaches of Forever - Tu Shan in 19 AD;
III, The Comrade - Rufus, in conversation with Lugo/Hanno, in 359 AD;
IV, Death in Palmyra - Aliyat in 641 AD.

Hanno was already over five hundred years old, an experienced immortal, in 310 BC - born during the reign of Hiram of Tyre. Various works of fiction have accustomed us to the idea that immortals move and change their identity to conceal their longevity every few decades but Anderson shows us Rufus and Aliyat before they have realized the need for this. They can only arouse wonder and suspicion among their contemporaries.