Lagrangian Aspects of the Kirchhoff Elastic Rod. - Joel Langer; David A. Singer (SIAM Rev., 1996)

Straightening soliton curves. - Joel Langer (Appl. Math. Lett., 2001)

Rational diffeomorphisms of the circle. - Joel Langer (Appl. Math. Lett., 2007)

Schwarz Reflection Geometry II: Local and Global Behavior of the Exponential Map. - Annalisa Calini; Joel Langer (Exp. Math., 2007)

When Is a Curve an Octahedron? - Joel Langer; David A. Singer (Am. Math. Mon., 2010)

Confocal Families of Hyperbolic Conics via Quadratic Differentials. - Joel Langer; David A. Singer (Axioms, 2023)

Orthogonal Families of Bicircular Quartics, Quadratic Differentials, and Edwards Normal Form. - Joel Langer; David A. Singer (Axioms, 2024)