Wang, JC; Carpenter, JR; Kepler, MA; (2006) Using SAS to conduct nonparametric residual bootstrap multilevel modeling with a small number of groups. Computer methods and programs in biomedicine, 82 (2). pp. 130-143. ISSN 0169-2607 DOI: https://doi.org/10.1016/j.cmpb.2006.02.006 Full text not available from this repository.