Gemfile in scholarmarkdown-1.3.1 vs Gemfile in scholarmarkdown-1.4.0

@@ -6,9 +6,15 @@
 gem 'latex-decode'
 gem 'citeproc-ruby', '>= 1.1.6'
 gem 'csl-styles'
 gem 'bibmarkdown', '~> 2.0.0'
 
+# math
+gem 'katex'
+gem 'sskatex'
+gem 'execjs'
+gem 'therubyracer' # embedded V8 JavaScript engine
+
 group :development do
   # management of this gem
   gem "bundler", "~> 1.0"
   gem "juwelier", "~> 2.4.7"
 end