On the use of dimensioned measures of error to evaluate the performance of spatial interpolators. - Cort J. Willmott; Kenji Matsuura (Int. J. Geogr. Inf. Sci., 2006)

Assessment of three dimensionless measures of model performance. - Cort J. Willmott; Scott M. Robeson; Kenji Matsuura; Darren L. Ficklin (Environ. Model. Softw., 2015)