Comment: Quaternionic, complex, duplex and real Clifford algebras (Q1842501)

The so-called ``duplex'' algebra is the real group ring \(\mathbb{D} = \mathbb{R} C\) of the cyclic group of order 2. Using the elementary fact that \(\mathbb{D} \cong \mathbb{R} \oplus \mathbb{R}\) as a ring, the author makes a trivial notational amendment to the table of Clifford algebras. Most of the paper is devoted to a resumé of well known results on Clifford algebras. There are many misprints.