Could not find a declaration file for module 'react-split-grid'.

I'm using create-react-app with the typescript template, and after installing npm install --save react-split-grid, and using the render style import, I am getting an error:

Could not find a declaration file for module 'react-split-grid'. 'C:/.../app/node_modules/react-split-grid/dist/react-split-grid.js' implicitly has an 'any' type.
  Try `npm install @types/react-split-grid` if it exists or add a new declaration (.d.ts) file containing `declare module 'react-split-grid';`  TS7016

    3 | import "./App.css";
    4 |
  > 5 | import Split from "react-split-grid";
      |                   ^

Any ideas? I do see https://github.com/nathancahill/split/blob/master/packages/splitjs/index.d.ts - any way to install that in parallel?