 In Space, Number, and Geometry from Helmholtz to Cassirer, Francesca Biagioli (2016) analyzes Helmholtz’s theories of geometry and of measurement, including their origins in the work of Kant, Riemann, and Gauss, and the reception, development, and extension of Helmholtz’s work through engagement with Felix Klein’s Erlanger Programm, Sophus Lie’s theory of groups, the conventionalism of Henri Poincaré, and neo-Kantian reception in Alois Riehl, Hermann Cohen, Ernst Cassirer, and Bruno Bauch. 