Kreinovich, Vladik Max Planck Institute for Mathematics, Max Planck Society;
Kreinovich, V., & Kosheleva, O. (2008). From (idealized) exact causality-preserving transformations to practically useful approximately-preserving ones: a general approach. International Journal of Theoretical Physics, 47(4), 1083-1091. doi:10.1007/s10773-007-9536-6.