diff --git a/bibliography.bib b/bibliography.bib
index 5754edb..7a64685 100644
--- a/bibliography.bib
+++ b/bibliography.bib
@@ -11,18 +11,13 @@ @InProceedings{martinlof1971hauptsatz
   Pages     = {179 -- 216},
 }
 
-@incollection{Martin-Lof-1972,
-	Author = {Martin-L{\"o}f, Per},
-	Booktitle = {Twenty-five years of constructive type theory ({V}enice, 1995)},
-	Mrclass = {03B15 (03F55)},
-	Mrnumber = 1686864,
-	Pages = {127--172},
-	Publisher = {Oxford University Press},
-        Editor = {Giovanni Sambin and Jan M. Smith},
-	Series = {Oxford Logic Guides},
-	Title = {An intuitionistic theory of types},
-	Volume = 36,
-	Year = 1998}
+@techreport{Martin-Lof-1972,
+  Author      = {Martin-L{\"o}f, Per},
+  Title       = {An intuitionistic theory of types},
+  institution = "University of Stockholm",
+  year        = "1972"
+}
+
 
 @incollection{Martin-Lof-1973,
 	Author = {Martin-L{\"o}f, Per},