diff --git a/docs/introduction.rst b/docs/introduction.rst
index df107cf..a83cbdf 100644
--- a/docs/introduction.rst
+++ b/docs/introduction.rst
@@ -6,26 +6,26 @@ Where do the Four Opens originate from? They came from a need to do things
 differently.
 
 Free software started in the 80’s by defining four (initially three)
-freedoms [1]_ that any free software should grant its users. Freedom 0 was the
-freedom to run the program as you wish, for any purpose. Freedom 1 was the
-freedom to study how the program works, and change it so it does your computing
-as you wish. Freedom 2 was the freedom to redistribute copies so you can help
-your neighbor. Freedom 3 was the freedom to distribute copies of your modified
-versions to others. Those freedoms made you free to improve the program, and
-release your improvements to the public, so that the whole community benefits.
-But free software did not mandate anything about how the software was to be
-built to actually encourage this collaboration across boundaries that would
-result in benefiting the whole community.
+freedoms [#fourfreedoms]_ that any free software should grant its users. Freedom
+0 was the freedom to run the program as you wish, for any purpose. Freedom 1
+was the freedom to study how the program works, and change it so it does your
+computing as you wish. Freedom 2 was the freedom to redistribute copies so you
+can help your neighbor. Freedom 3 was the freedom to distribute copies of your
+modified versions to others. Those freedoms made you free to improve the
+program, and release your improvements to the public, so that the whole
+community benefits.  But free software did not mandate anything about how the
+software was to be built to actually encourage this collaboration across
+boundaries that would result in benefiting the whole community.
 
 When open source was defined in 1998, it focused on a specific angle (the one
 that mattered the most to businesses), which is the availability and
 re-usability of the code. That also said remarkably little about how the
-software should be built, and nothing about who really controls it. As a
-result by 2010 most open source projects were actually closed one way or
-another: their core development may be done behind closed walls, or their
-governance may be locked down to ensure control by its main sponsor. Sure,
-their end product was licensed under an open source license, but those were not
-really community projects anymore. 
+software should be built, and nothing about who really controls it. As a result
+by 2010 most open source projects were actually closed one way or another:
+their core development may be done behind closed walls, or their governance may
+be locked down to ensure control by its main sponsor. Sure, their end product
+was licensed under an open source license, but those were not really community
+projects anymore. 
 
 The control of a specific party over the code is discouraging contributors to
 participate: those are seen as free labor and are not on a level playing field
@@ -55,13 +55,13 @@ open source cloud infrastructure platform available.
 
 It was from these conditions that "The Four Opens" were born. The first public
 mention of them was posted on the then-nascent OpenStack Wiki on June 28,
-2010[1]_, before OpenStack was even publicly discussed or announced. The
-titles of the Four Opens (Open source, Open Design, Open Development, Open
-Community) were set from that day. The content evolved a bit over time on the
-Wiki, as implementation details rolled in (for example: public code reviews,
-design summits, technical committee, lazy and consensus). The Four Opens
-description is now maintained officially in the OpenStack governance
-web-site[2]_.
+2010 [#fouropenswiki]_, before OpenStack was even publicly discussed or
+announced. The titles of the Four Opens (Open source, Open Design, Open
+Development, Open Community) were set from that day. The content evolved a bit
+over time on the Wiki, as implementation details rolled in (for example: public
+code reviews, design summits, technical committee, lazy and consensus). The
+Four Opens description is now maintained officially in the OpenStack governance
+web-site [#fouropens]_.
 
 After eight years, the Four Opens proved pretty resilient, consistently
 managing to capture the "OpenStack Way" of doing upstream open source
@@ -74,5 +74,6 @@ generally support Open Infrastructure, the Four Opens will grow beyond
 OpenStack. Let's apply them to other nascent open source projects with the same
 success.
 
-[1]_ https://wiki.openstack.org/w/index.php?title=Open&oldid=9628
-[2]_ https://governance.openstack.org/tc/reference/opens.html
+.. [#fourfreedoms] https://www.gnu.org/philosophy/free-sw.en.html
+.. [#fouropenswiki] https://wiki.openstack.org/w/index.php?title=Open&oldid=9628
+.. [#fouropens] https://governance.openstack.org/tc/reference/opens.html