diff --git a/README.md b/README.md
index 223ca57a..ce62495c 100644
--- a/README.md
+++ b/README.md
@@ -4,16 +4,11 @@ title: About
 permalink: /about/
 ---
 
-This book is an introduction to programming language theory, written
-in Agda.  The authors are [Wen Kokke][wen] and [Philip Wadler][phil].
+This book is an introduction to programming language theory, written in Agda.  The authors are [Wen Kokke][twitter.com/wenkokke] and [Philip Wadler][twitter.com/PhilipWadler].
 
-Please send us comments!  The text is currrently being drafted. The
-first draft of Part I will be completed before the end of
-March 2018. When that is done it will be announced here, and that would be
-an excellent time to comment on the first part.
+Please send us comments!  The text is currrently being drafted. The first draft of Part I will be completed before the end of March 2018. When that is done it will be announced here, and that would be an excellent time to comment on the first part.
 
-The book was inspired by [Software Foundations][sf], but presents the
-material in a different way; see the [Preface](Preface).
+The book was inspired by [Software Foundations][softwarefoundations.cis.upenn.edu], but presents the material in a different way; see the [Preface](Preface).
 
 ## How to host literate code
 
@@ -54,12 +49,6 @@ See [the emacs-mode docs]( http://agda.readthedocs.io/en/latest/tools/emacs-mode
 
 ## Markdown
 
-For an overview of the Markdown syntax, see [the original description](
-https://daringfireball.net/projects/markdown/syntax
-), [the CommonMark project](
-http://spec.commonmark.org/0.28/
-), or [the version that is used in this book](
-https://kramdown.gettalong.org/syntax.html
-).
+For an overview of the Markdown syntax, see [the original description](daringfireball.net/projects/markdown/syntax), [the CommonMark project](spec.commonmark.org/0.28/), or [the version that is used in this book](kramdown.gettalong.org/syntax.html).