∇ | Nabla Symbol (Meaning, How To Type on Keyboard, & More) - Symbol Hippo
ferraridamiano (Damiano Ferrari) · GitHub
symbols - Looking for \mathbb style $\Delta$ and $\nabla$ - TeX - LaTeX Stack Exchange
LATEX Mathematical Symbols
Fermat's Library on Twitter: "The nabla symbol, commonly used in math to represent the gradient of a function ∇f, is so-called because it looks like a harp and the Greek word for