Dutch-Indonesian singer and musician Riem De Wolff, who with his late brother Rudy made up 1960s pop duo The Blue Diamonds, died in the Netherlands yesterday morning. He was 74.

The duo's renditions of pop songs such as Ramona and Oh Carol were popular among Singapore music fans in the early 1960s and they had also played here several times since they made their debut live show here in 1960.

De Wolff married a Singaporean, Ms Shireen Swan, in the mid-1990s and the couple shuttled between Singapore and Holland.

Veteran Singaporean singer Vernon Cornelius, a close friend of De Wolff's, received a text from Ms Swan to inform him of her husband's death.

According to Cornelius, De Wolff was diagnosed with cancer in his lungs and liver less than two weeks ago, a few days after he played his last gig in the Netherlands. He last performed in Singapore at a New Year's Eve show last year at the Tanah Merah Country Club with Cornelius.

The Blue Diamonds, also known as the European Everly Brothers, sang in English, German, French and Spanish and sold 14 million records during their career. Rudy died of bladder cancer in 2000.

Cornelius said De Wolff and The Blue Diamonds influenced many singers and musicians in Singapore. "He taught me everything I knew about singing," he said.

"I was one of the fans who would chase him around when they played in Singapore in the early 1960s and I learnt how to sing in harmony by listening to their records."

De Wolff also leaves behind a son and daughter from a previous marriage.