I need help researching Colne Titanic hero Wallace Hartley | Burnley Express letters

I am researching Maria Robinson who was born in 1880 in Leeds, Yorkshire, West Riding and died in 1939 in Bridlington, Yorkshire for an upcoming book on women connected to the Titanic.

Her fiancé was Colne’s Wallace Hartley, bandmaster on the Titanic. He died in the sinking. Maria had given him a violin and case as an engagement present. When Maria died, her sister Miss Margaret Robinson gave it to the Bridlington Salvation Army, and it went to a violin teacher after that. After being authenticated, it was sold in 2013 and is in a Titanic museum in the United States.

Maria was given a gold locket by Wallace, and it was recently (2021) sold at auction by Henry Aldridge and Sons by a great-niece of Miss Robinson.

I would also like to find a copy of the book Nearer, Our God, to Thee: The Biography of the Titanic Bandmaster (2013) by Christian G. Tennyson-Ekeberg or how to contact Mr. Tennyson-Ekeberg .I would like any information on Maria or anyone to contact who might have known the Robinson family and their story.

Thank you so much for any help or direction you can give me.