According to: http://mirrors.ibiblio.org/CTAN/fonts/newtx/doc/newtxdoc.pdf
The package invoked by \usepackage{newtxmath} loads the math part of the txfonts (with revised metrics and additional glyphs) and should be loaded after the text font and its encoding have been specified, as it uses the text font settings to define how operators, numbers, math accents, \mathrm, \mathbf etc. are rendered But if I select document/settings/fonts/Math: Times Roman (New TX) Generated TeX says: \documentclass[american,journal,comsoc]{IEEEtran} \usepackage{amsmath} \usepackage{newtxmath} \usepackage[T1]{fontenc} \usepackage[latin9]{luainputenc} Is this OK? Does \usepackage{newtxmath} need to be moved later in the preamble?