Install docbook-mathml by entering the following commands in the terminal:
sudo apt update sudo apt install docbook-mathml
Description:
Extension to DocBook XML for using MathML markup
The DocBook MathML module adds support for including MathML markup in DocBook XML source documents. . The MathML module is a customization of the full DocBook XML V4.1.2 DTD. The module requires access to the MathML V2.0 DTD provided by the w3-dtd-mathml package.
Homepage: http://www.oasis-open.org/docbook/xml/mathml/
Version: 1.1CR1-2
Section: universe/text