$ yarn add --dev @types/bitgo-utxo-lib
yarn add v1.16.0
[1/5] Validating package.json...
[2/5] Resolving packages...
error An unexpected error occurred: "https://registry.npmjs.org/@types%2fbitgo-utxo-lib: Not found".
info If you think this is a bug, please open a bug report with the information provided in "yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.