The phrase "maintained a correspondence" is correct and usable in written English.
You would use it to describe a situation in which two or more people have exchanged written messages, such as letters, emails, or text messages, over an extended period of time. For example: "For ten years, my pen pal and I have maintained a correspondence, exchanging letters on a weekly basis."
Was he a hermaphrodite?" Tahira secretly maintained a correspondence with Nehru.
Winston Churchill and Wells maintained a correspondence too, though many of their letters have been lost.
Juan studied under Spain's leading Humanists and developed religious views that closely followed the ideas of Erasmus of Rotterdam, with whom both he and his brother maintained a correspondence.
In consequence, after the king's execution her arrest was ordered on March 21 , 1649 and she was imprisoned in the Tower, whence she maintained a correspondence in cipher with Charles through her brother, Lord Percy, until Charles went to Scotland.
Back in the 8th century, the prestige of King Offa during the "Mercian Supremacy" was recognised not only in England but on the continent, where he maintained a correspondence with Charlemagne, incomparably the most important lay figure of the period; Pope Hadrian was also a pal.
Jonze can't get over how Gonzales has maintained a correspondence with Jonze's mother since their brief meeting several years ago; and how, when he and Gonzales drive around Los Angeles, Gonzales insists on taking long detours to visit people he hardly knows, like "the older lady who worked at a coffee stand in Laguna Beach who he said was the coolest person".
Makgatho's first wife, Reyne, filled the gap, maintaining a correspondence with her father-in-law, but she divorced her husband and married an Englishman.
The hunky stuff of bodice-ripping fantasy, Frank maintains a correspondence with Ada after she becomes the unhappily married mother of several children.
She remained good friends with the Dawns, resisting their invitations to work in the United States because her mother needed her, she said, but maintaining a correspondence with Katherine Dawn for thirty-five years (Donaldson).
SYMRT follows the approach of SARTS [23] and TETASARTS [25] relying on TIMES for its theoretical framework but, as opposed to TIMES, maintains a correspondence between the analyzed code and the model.
Major correspondence of ten or more letters between those friends with whom Hendrik maintained a regular correspondence is included in this series.
