en Brown, George W. (). „Standard deviation, standard error: Which 'standard' should we use?”. American Journal of Diseases of Children. 136 (10): 937–941. doi:10.1001/archpedi.1982.03970460067015. PMID7124681.
en Brown, George W. (). „Standard deviation, standard error: Which 'standard' should we use?”. American Journal of Diseases of Children. 136 (10): 937–941. doi:10.1001/archpedi.1982.03970460067015. PMID7124681.