Stephen Hawking, "A Brief History of Time", Chapter 3: "Now imagine a source of light at a constant distance from us, such as a star, emitting waves of light at a constant wavelength. Obviously the wavelength of the waves we receive will be the same as the wavelength at which they are emitted (the gravitational field of the galaxy will not be large enough to have a significant effect). Suppose now that the source starts moving toward us. When the source emits the next wave crest it will be nearer to us, so the distance between wave crests will be smaller than when the star was stationary." http://www.fisica.net/relatividade/stephen_hawking_a_brief_history_of_time.pdf
This interpretation, universally taught by Einsteinians, implies that the speed of the wavecrests relative to the moving source is smaller than c - unlike the stationary source, the moving source is chasing the fleeing wavecrest. Accordingly, the following argument is valid:
Premise 1: The speed of the wavecrests relative to both the stationary and the moving source is c.
Premise 2: The frequency measured by the observer is higher when the source is moving toward the observer.
Conclusion: The moving source does not emit shorter wavelength - rather, it emits faster light. If the speed of the moving source is v, the speed of the light relative to the observer is c'=c+v. In other words, the speed of light varies with the speed of the source, as predicted by Newton's emission theory of light and in violation of Einstein's relativity.