The work of independent artists was also influenced by the crises of the Dust Bowl and the Depression. Author John Steinbeck, wrote "The Grapes of Wrath" (1939) about migrant workers and farm families displaced by the Dust Bowl. Babb's own novel about the lives of the migrant workers, "Whose Names Are Unknown", was written in 1939 but was eclipsed and shelved in response to the success of Steinbeck's work, and was finally published in 2004. Many of the songs of folk singer Woody Guthrie, such as those on his 1940 album "Dust Bowl Ballads", are about his experiences in the Dust Bowl era during the Great Depression when he traveled with displaced farmers from Oklahoma to California and learned their traditional folk and blues songs, earning him the nickname the "Dust Bowl Troubadour".