Kees Storm on Twitter: "There is enough ugliness in the world. Please help end the abomination that is the default angle bracket, and use \rangle and \langle instead. What is your favorite #
Left Angle Bracket(⟨) symbol in LaTeX | Latexhelp
Brackets Symbols (){} 〈 〉【 】〚 〛Bracket Alt Codes
math mode - How to get double angle bracket without using MnSymbol package? - TeX - LaTeX Stack Exchange