diff --git a/dosp-survey.ltx b/dosp-survey.ltx
index 27d9ca7ffc9aa5e9a2d9a781cf23592a8587d451..fe018003cb2a7d763ec49e81f7c6aa83c16ed163 100644
--- a/dosp-survey.ltx
+++ b/dosp-survey.ltx
@@ -270,7 +270,9 @@ permissive (BSD-style) license grant that later transforms into a
 reciprocal (GPL-style) license. This is intended to allow downstream
 code reuse in proprietary software projects, but only for a limited
 time, something Zooko characterized as a compromise between
-permissive and reciprocal open source licensing models.
+permissive and reciprocal open source licensing models.\footnote{See,
+for example, the presentation at
+\otsurl{https://tahoe-lafs.org/~zooko/tgppl.pdf}.}
 
 Since both the start and end-state licenses of the BOSL are themselves
 open source, we do not regard the BOSL as a form of delayed open source
@@ -331,8 +333,9 @@ Many people also mentioned the custom among some video game developers of
 releasing code (though usually not assets such as graphics and sound)
 from proprietary video games that are no longer commercially important.
 This is a relatively widespread practice, with Wikipedia identifying
-dozens of instances.
-% TODO \cite{Wikipedia}
+dozens of instances.\footnote{Wikipedia lists these examples at
+\otsurl{https://en.wikipedia.org/wiki/List\_of\_commercial\_video\_games\_with\_later\_released\_source\_code}.}
+
 Some companies like id Software have made such releases for multiple video
 game generations.
 While many of these developers apparently had a general intention to make
@@ -341,7 +344,6 @@ there was usually no public commitment to do so on any particular
 schedule or under any particular circumstances.  This practice is thus not
 a core example of DOSP.
 
-
 \numberedsection{Sources and References}\label{sources}
 
 \begin{itemize}
@@ -352,8 +354,6 @@ a core example of DOSP.
 
 % https://writing.kemitchell.com/2023/10/24/Scheduled-Relicensing
 
-% https://tahoe-lafs.org/~zooko/tgppl.pdf
-
   \item \otscite{Wikipedia: List of Commercial Video Games With Later Released Source Code}\\
 	\otsurl{https://en.wikipedia.org/wiki/List\_of\_commercial\_video\_games\_with\_later\_released\_source\_code}