diff --git a/ippisite/ippidb/views/contribute.py b/ippisite/ippidb/views/contribute.py
index 0b2a786c6f8f31295d4d59b19ba4994de3682926..2639b9d7de3c5d636fd99697c85321f50bc11760 100644
--- a/ippisite/ippidb/views/contribute.py
+++ b/ippisite/ippidb/views/contribute.py
@@ -5,7 +5,7 @@ iPPI-DB contribution views
 from django.contrib.auth.mixins import LoginRequiredMixin
 from django.db import transaction
 from django.forms import model_to_dict
-from django.shortcuts import render
+from django.shortcuts import render, get_object_or_404
 from django.utils.translation import ugettext_lazy
 from formtools.wizard.views import NamedUrlSessionWizardView
 
@@ -316,7 +316,7 @@ class IppiWizard(LoginRequiredMixin, NamedUrlSessionWizardView):
 def admin_session_view(request, bibli_pk, ppi_pk):
     context = {}
     if bibli_pk:
-        bibliography = models.Bibliography.objects.get(pk=bibli_pk)
+        bibliography = get_object_or_404(models.Bibliography, pk=bibli_pk)
         context["bibliography"] = bibliography
         context["testactivitydescription"] = bibliography.testactivitydescription_set.all()
         context["testcytotoxdescription"] = bibliography.testcytotoxdescription_set.all()
@@ -324,7 +324,7 @@ def admin_session_view(request, bibli_pk, ppi_pk):
         context["refcompoundbiblio"] = bibliography.refcompoundbiblio_set.all()
 
     if ppi_pk:
-        ppi = models.Ppi.objects.get(pk=ppi_pk)
+        ppi = get_object_or_404(models.Ppi, pk=ppi_pk)
         context["ppi"] = ppi
         context["complexes"] = ppi.ppicomplex_set.all()