Probably the first appearance of the 3-fractions puzzle in the constraints literature is [schulte2004finite].

The following paper shows how a basic model of the 3-fractions puzzle can be improved automatically [frisch2001extensions].

Using hand-reformulation, the following paper discusses how different using symmetry-breaking schemes on the 3-fractions puzzle, followed by the derivation of implied constraints, can lead to models of varying quality [frisch2004symmetry].

[schulte2004finite]

Finite Domain Constraint Programming in Oz. A Tutorial.

Available at www. mozart-oz. org,
2004

[frisch2004symmetry]

Symmetry breaking as a prelude to implied constraints: A constraint modelling pattern

ECAI, 171,
2004

[frisch2001extensions]

Extensions to proof planning for generating implied constraints

In Proceedings of Calculemus-01,
2001