Special relativity (alternative formulations)
Hendrik Lorentz and Henri Poincaré developed their version of special relativity in a series of papers from about 1900 to 1905. They used Maxwell's equations and the principle of relativity to deduce a theory that is mathematically equivalent to the theory later developed by Einstein.
Aether drag hypothesis
However, the accumulation of hypotheses to rescue the stationary aether concept was considered to be very artificial. So it was Albert Einstein (1905), who recognized that it is only required to assume the principle of relativity and the constancy of the speed of light in all inertial frames of reference, in order to develop the theory of special relativity and to derive the complete Lorentz transformation. All this was done without using the stationary aether concept.