[1] UNIV CALIF BERKELEY, SCH OPTOMETRY, BERKELEY, CA 94720 USA
[2] OHIO STATE UNIV, COLL OPTOMETRY, COLUMBUS, OH 43210 USA
[3] HARVARD UNIV, CHILDRENS HOSP, SCH MED, DEPT OPHTHALMOL, BOSTON, MA 02115 USA
[4] NEW ENGLAND COLL OPTOMETRY, BOSTON, MA USA
[5] PENN COLL OPTOMETRY, PHILADELPHIA, PA 19141 USA
[6] NE STATE UNIV, COLL OPTOMETRY, TAHLEQUAH, OK USA
[7] UNIV ARIZONA, DEPT OPHTHALMOL, TUCSON, AZ 85721 USA
[8] UNIV PENN, SCHEIE EYE INST, DEPT OPHTHALMOL, PHILADELPHIA, PA 19104 USA