Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Such $f$ exists on anyevery open Riemann surface:
R.C. Gunning and R. Narasimhan. Immersion of open Riemann surfaces. Math. Ann., 174:103–108, 1967.
Such $f$ exists on any open Riemann surface:
Such $f$ exists on every open Riemann surface:
