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Certain Topics in Telegraph Transmission Theory by Nyquist (1928) might be what you're looking for (emphasis mine):


  The following topics are discussed:
  
  
  The required frequency band is directly proportional to the signaling speed.
  A repeated telegraph signal (of any length) may be considered as being made up of sinusoidal components. When the amplitude and phase,
  or real and imaginary parts, of these components are plotted as
  ordinates with their frequencies as abscissas, and when the frequency
  axis is divided into parts each being a frequency band of width
  numerically equal to the speed of signaling, it is found that the
  information conveyed in any band is substantially identical with that
  conveyed in any other; and the bands may be said to be mutually
  redundant.
  The minimum band width required for unambiguous interpretation is substantially equal, numerically, to the speed of signaling and is
  substantially independent of the number of current values employed.
  A criterion of perfect transmission is selected; and a discussion is given of the characteristics which the received wave must have to
  be nondistorting with the requirement that the frequency range should
  not be greater than necessary.
  Directions are sketched for specifying systems to meet this requirement.
  Several alternative criteria of distortionless transmission are considered and a method for computing the corresponding transmission
  characteristics of the circuit is explained and illustrated.
  An analysis is given of the carrier wave, and it is shown that the usual carrier telegraph requires twice as much frequency range as the
  corresponding d-c. telegraph, other things being equal.
  A discussion is given of two alternative methods for overcoming this inefficiency of carrier telegraphy, namely, the use of phase
  discrimination and of a single sideband.
  After the d-c. and carrier waves have thus been analyzed a corresponding analysis is given of an arbitrary wave shape, including
  these two as special cases. Calculations are given on the shaping of
  the transmitted wave so as to make the received wave perfect.
  A discussion is given of the dual aspect of the telegraph wave. The wave may be looked on either as a function of , requiring the
  so-called steady-state method of treatment, or as a function of
  requiring the so-called method of transients. It is shown that the
  steady-state theory can be made to yield the information necessary to
  specify the characteristics of an ideal system.
  A discussion is given of the effect of interference and departures from ideal conditions.