Install icu-doc by entering the following commands in the terminal:
sudo apt update sudo apt install icu-doc
Description:
API documentation for ICU classes and functions
ICU is a C++ and C library that provides robust and full-featured Unicode and locale support. This package contains HTML files documenting the ICU APIs.
Homepage: http://www.icu-project.org
Version: 60.2-3ubuntu3
Section: doc