[1] Mayo Clin, Sleep Disorders Ctr, Rochester, MN 55905 USA
[2] Detroit VA Med Ctr, Detroit, MI USA
[3] Natl Jewish Med & Res Ctr, Denver, CO USA
[4] Univ Calif Los Angeles, Greater Los Angeles VA Healthcare Syst, Sepulveda, CA USA
[5] Univ N Carolina, Chapel Hill, NC 27515 USA
[6] St Joseph Mem Hosp, Murphysboro, IL USA
[7] Stanford Univ, Stanford, CA 94305 USA
[8] Univ Washington, Seattle, WA 98195 USA
[9] Rhode Isl Hosp, Providence, RI 02903 USA
[10] Houston Sleep Ctr, Houston, TX USA