Haluska, Ján (2003). The Mathematical Theory of Tone Systems, Pure and Applied Mathematics Series 262 (New York: Marcel Dekker; London: Momenta), p. xxiii. ISBN 0824747143. "7/5 septimal or Huygens' tritone, Bohlen-Pierce fourth", "10/7 Euler's tritone".
Partch, Harry. (1974). Genesis Of A Music: An Account of a Creative Work, Its Roots and Its Fulfillments, second edition, enlarged (New York: Da Capo Press): p. 69. ISBN 030671597X (cloth); ISBN 030680106X (pbk).
Renold, Maria (2004). Intervals, Scales, Tones and the Concert Pitch C=128Hz, translated from the German by Bevis Stevens, with additional editing by Anna R. Meuss (Forest Row: Temple Lodge): p. 15–16. ISBN 1902636465.
Helmholtz, Hermann von (2005). On the Sensations of Tone as a Physiological Basis for the Theory of Music, p. 457. ISBN 1419178938. "Cents in interval: 590, Name of Interval: Just Tritone, Number to an Octave: 2.0. [Cents:] 612, [Name:] Pyth.[agorean] Tritone, [per octave:] 2.0."
Strange, Patricia and Patricia, Allen (2001). The contemporary violin: Extended performance techniques, p. 147. ISBN 0520224094. "...septimal tritone, 10:7; smaller septimal tritone, 7:5;...This list is not exhaustive, even when limited to the first sixteen partials. Consider the very narrow augmented fourth, 13:9....just intonation is not an attempt to generate necessarily consonant intervals."