Alternative stream ordering systems have been developed by ShreveShreve, R.L., 1966. Statistical law of stream numbers. Journal of Geology 74, 17–37.Shreve, R.L., 1967. Infinite topologically random channel networks. Journal of Geology 75, 178–186. and Hodgkinson et al.Hodgkinson, J.H., McLoughlin, S. & Cox, M.E. 2006. The influence of structural grain on drainage in a metamorphic sub-catchment: Laceys Creek, southeast Queensland, Australia. Geomorphology, 81: 394–407. A statistical comparison of Strahler and Shreve systems, together with an analysis of stream/link lengths, is given by Smart.Smart, J.S. 1968, Statistical properties of stream lengths, Water Resources Research, 4, No 5. 1001–1014
