LOS ANGELES: A collection of love letters written by Canadian musician Leonard Cohen to the woman who inspired his song, "So Long, Marianne" is going up for auction next month, two years after both of them died. The archive of 50 letters from Cohen to Marianne Ihlen chronicles their 1960s love affair and the blossoming of Cohen's career from struggling poet to famous singer-songwriter, Christie's New York auction house said on Wednesday. The letters are being sold by Ihlen's family. Cohen and Norwegian-born Ihlen met on the Greek island of Hydra in 1960 and she became the inspiration for several of his best-known songs, including "Bird on a Wire," "Hey, That's No Way to Say Goodbye," and the 1967 track, "So Long, Marianne." Ihlen died of leukaemia in Oslo in July 2016 at age 81. Cohen, in a letter to her before her death, wrote, "Endless love, see you down the road." Cohen, who was also suffering from leukaemia, died in November 2016 at the age of 82. The letters are postmarked from Hydra, Montreal, London, New York and Tel Aviv, and continue into the 1970s, years after their romantic relationship ended. In a December 1965 letter, Cohen writes after a quarrel: "Is there any fire left?" In a February 1967 letter, Cohen writes of his first major performance: “I sang in New York for the first time last night, at a huge benefit concert. Every singer you’ve ever heard of was there performing. Judy Collins introduced me to the audience, over 3000 people." The letters will be sold as individual lots, at $300-$12,000 each. The auction will take place online from June 5-13.