He kept up a lengthy correspondence with Olaf Stapledon.

This letter was the start of a lengthy correspondence.

A response from Ryle and a lengthy correspondence ensued.

In the 1980s, he carried on a lengthy correspondence with convicted child serial killer Clifford Olson.

How their lengthy correspondence got into my grubby little hands I do not wish to go into at this point.

Ricardo and Malthus debated this in a lengthy personal correspondence.

This generated a lifetime of lengthy correspondence with the former in addition to comprehensive instruction on the art of poetry from Pound.

A lengthy correspondence between the two, finally led to an agreement upon holding a debate, on the basic issue or dispute: i.e.

Cleary carried on a lengthy correspondence in the daily press defending the Catholic position.

They never met, but kept up a lengthy correspondence that shows their growing admiration, esteem and friendship.