diff --git a/radar/2017-03-01/sass.md b/radar/2017-03-01/sass.md
index 75d883c..2624324 100644
--- a/radar/2017-03-01/sass.md
+++ b/radar/2017-03-01/sass.md
@@ -15,7 +15,7 @@ Core features of SASS are:
 *   Extends: CSS properties can be inherited
 *   SASS files can be split into modules, which leads to smaller files and better file structures
 *   Operators: Simple math calculations can be applied to CSS properties
-*   Easily to integrate in nodejs-environments and build tools such s [NPM](/tools/npm.html), [Gulp](/tools/gulp.html) and [Grunt](/tools/grunt.html).
+*   Easily to integrate in nodejs-environments and build tools such s [NPM](https://www.npmjs.com/), [Gulp](http://gulpjs.com/) and [Grunt](https://gruntjs.com/).
 
 SASS has been widely adopted for many years and has evolved to an industry-standard backed by an active community since 2006.
 
@@ -27,4 +27,4 @@ More information:
 
 *   [SASS Language](http://sass-lang.com/)
 *   [SASSDoc](http://sassdoc.com/)
-*   [Improving Sass code quality on](https://www.theguardian.com/info/developer-blog/2014/may/13/improving-sass-code-quality-on-theguardiancom) [theguardian.com](http://theguardian.com)
\ No newline at end of file
+*   [Improving Sass code quality on](https://www.theguardian.com/info/developer-blog/2014/may/13/improving-sass-code-quality-on-theguardiancom) [theguardian.com](http://theguardian.com)