Question: Are Adam Gontier and Björk both singers?
Related documents: [0]  [DOC] Adam Wade Gontier (born May 25, 1978) is a Canadian singer, songwriter and musician. He is the lead singer, rhythm guitarist and main songwriter for Saint Asonia, but is best known as the former lead singer, rhythm guitarist and main songwriter of the Canadian rock band Three Days Grace. Gontier left Three Days Grace on January 9, 2013. In addition to his work with Three Days Grace, he has been involved in collaborations with other bands including Art of Dying and Apocalyptica. [END] 
[1]  [DOC] Björk Guðmundsdóttir (] , born 21 November 1965), known as Björk ( ), is an Icelandic singer, songwriter, actress, record producer, and DJ. Over her four-decade career, she has developed an eclectic musical style that draws on a wide range of influences and genres spanning electronic, pop, experimental, classical, trip hop, IDM, and avant-garde styles. She initially became known as the lead singer of the alternative rock band The Sugarcubes, whose 1987 single "Birthday" was a hit on US and UK indie stations and a favorite among music critics. Björk embarked on a solo career in 1993, coming to prominence as a solo artist with albums such as "Debut" (1993), "Post" (1995), and "Homogenic" (1997), while collaborating with a range of artists and exploring a variety of multimedia projects. [END] 
Answer: 
yes
yes