Marianne Ihlen died last week (ends29Jul16) and Jan Christian Mollestad, who is currently completing a biographical film about her, informed the songwriter.

In a Facebook post, Cohen has asked that Mollestad's letter to him about his friend's passing be read at her memorial.

He wrote: "Marianne slept slowly out of this life yesterday evening. Totally at ease, surrounded by close friends."

Mollestad also recalled Cohen's letter to his former muse, which he read to her in her final days.

"Your letter came when she still could talk and laugh in full consciousness," he writes. "When we read it aloud, she smiled as only Marianne can. She lifted her hand, when you said you were right behind, close enough to reach her."

"In her last hour I held her hand and hummed Bird on a Wire, while she was breathing so lightly," Mollestad adds. "And when we left the room, after her soul had flown out of the window for new adventures, we kissed her head and whispered your everlasting words, So long, Marianne."

Cohen's Facebook manager has also created an ongoing memorial to Ihlen on the singer/songwriter's social media site, stating: "The woman immortalized in So Long, Marianne has evoked an overwhelming response from those who knew Marianne well, those who knew her only as Leonard Cohen's muse, and even those who previously didn't know there was a 'real Marianne'."