Celerion, Tempe, Arizona, United States
Woodland International Research Group, Inc, Little Rock, Arkansas, United States
Clinical Trials of Texas, Inc., San Antonio, Texas, United States
Synergy Clinical Research, National City, California, United States
University Hospital and School of Medicine, Olomouc, Czech Republic
Faculty Hospital Motol, Prague, Czech Republic
Helsinki University Hospital, Helsinki, Finland
Sleep Disorders Center of Georgia, Atlanta, Georgia, United States
Clinilabs, Inc., New York, New York, United States
Tri-State Sleep Disorders Center, Cincinnati, Ohio, United States
Charlotte Neurosurgical Associates, Charlotte, North Carolina, United States
UCSD Thornton Hospital, La Jolla, California, United States
Emory University Hospital - Atlanta, Atlanta, Georgia, United States