In the above paper <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> , there is a description on page 1, column 2 in the introduction section: “However, no practical demonstration of this has been reported yet, probably due to the complexity of integrating this Huygens metasurface with a practical LWA.”