diff --git a/core/facets.py b/core/facets.py
index bde8116d..bb959112 100644
--- a/core/facets.py
+++ b/core/facets.py
@@ -86,8 +86,10 @@ class BaseFacet(object):
         
 class FacetGroup(object):
     # a FacetGroup should implement title, facets, has_facet(self, facet_name) and get_facet_class(self, facet_name)
+        
     def has_facet(self, facet_name):
         return facet_name in self.facets
+        
     def get_facets(self):
         for facet_name in self.facets:
             yield self.get_facet_class(facet_name)(None)
@@ -104,7 +106,7 @@ class FormatFacetGroup(FacetGroup):
         super(FacetGroup,self).__init__()
         self.title = 'Format'
         self.facets = ['pdf', 'epub', 'mobi']
-        
+        self.label = '{} is ...'.format(self.title)
     
     def get_facet_class(self, facet_name):
         class FormatFacet(NamedFacet):
@@ -126,6 +128,37 @@ class FormatFacetGroup(FacetGroup):
             def description(self):
                 return  "These eBooks available in %s format." % self.facet_name
         return FormatFacet    
+
+idtitles = {'doab': 'indexed in DOAB', 'gtbg':'available in Project Gutenberg'}
+idlabels = {'doab': 'DOAB', 'gtbg':'Project Gutenberg'}
+class IdFacetGroup(FacetGroup):
+    def __init__(self):
+        super(FacetGroup,self).__init__()
+        self.title = 'Collection'
+        self.facets = idtitles.keys()
+        self.label = 'Included in ...'        
+    
+    def get_facet_class(self, facet_name):
+        class IdFacet(NamedFacet):
+            def set_name(self):
+                self.facet_name=facet_name
+            def id_filter(query_set):
+                return query_set.filter(identifiers__type=facet_name)
+            model_filters = {}
+            def get_query_set(self):
+                return self._get_query_set().filter(identifiers__type=self.facet_name)
+            def template(self):
+                return 'facets/id.html'
+            @property    
+            def label(self):
+                return idlabels[self.facet_name]
+            @property
+            def title(self):
+                return idtitles[self.facet_name]
+            @property
+            def description(self):
+                return  "These eBooks are {}.".format(idtitles[self.facet_name])
+        return IdFacet    
         
         
 class LicenseFacetGroup(FacetGroup):
@@ -134,6 +167,7 @@ class LicenseFacetGroup(FacetGroup):
         self.title = 'License'
         self.licenses = cc.LICENSE_LIST_ALL
         self.facets = cc.FACET_LIST
+        self.label = '{} is ...'.format(self.title)
         
         
     def get_facet_class(self, facet_name):
@@ -175,6 +209,7 @@ class KeywordFacetGroup(FacetGroup):
         self.title = 'Keyword'
         # make facets in TOPKW available for display
         self.facets = [('kw.%s' % kw) for kw in TOPKW]
+        self.label = '{} is ...'.format(self.title)
         
     def has_facet(self, facet_name):
     
@@ -209,7 +244,8 @@ class PublisherFacetGroup(FacetGroup):
         self.title = 'Publisher'
         # don't display facets
         self.facets = []
-        
+        self.label = 'Published by ...'
+
     def has_facet(self, facet_name):
     
         # recognize any facet_name that starts with "pub." as a valid facet name
@@ -249,7 +285,7 @@ class PublisherFacetGroup(FacetGroup):
         return PublisherFacet    
 
 # order of groups in facet_groups determines order of display on /free/    
-facet_groups = [KeywordFacetGroup(), FormatFacetGroup(),  LicenseFacetGroup(), PublisherFacetGroup()]
+facet_groups = [KeywordFacetGroup(), FormatFacetGroup(),  LicenseFacetGroup(), PublisherFacetGroup(), IdFacetGroup()]
 
 def get_facet(facet_name):
     for facet_group in facet_groups:
diff --git a/core/models/bibmodels.py b/core/models/bibmodels.py
index a758fdea..fe8e6c7b 100644
--- a/core/models/bibmodels.py
+++ b/core/models/bibmodels.py
@@ -45,9 +45,17 @@ from regluit.core.parameters import (
 logger = logging.getLogger(__name__)
 good_providers = ('Internet Archive', 'Unglue.it', 'Github', 'OAPEN Library')
 
+def id_for(obj, type):
+    if not obj.pk:
+        return ''
+    try:
+        return obj.identifiers.filter(type=type)[0].value
+    except IndexError:
+        return ''
+
 
 class Identifier(models.Model):
-    # olib, ltwk, goog, gdrd, thng, isbn, oclc, olwk, doab, gute, glue, doi
+    # olib, ltwk, goog, gdrd, thng, isbn, oclc, olwk, doab, gtbg, glue, doi
     type = models.CharField(max_length=4, null=False)
     value = models.CharField(max_length=250, null=False)
     work = models.ForeignKey("Work", related_name="identifiers", null=False)
@@ -110,6 +118,17 @@ class Work(models.Model):
     def __init__(self, *args, **kwargs):
         self._last_campaign = None
         super(Work, self).__init__(*args, **kwargs)
+    
+    def id_for(self, type):
+        return id_for(self, type)
+
+    @property
+    def gtbg(self):
+        return id_for(self, 'gtbg')
+
+    @property
+    def doab(self):
+        return id_for(self, 'doab')
 
     @property
     def googlebooks_id(self):
@@ -149,10 +168,7 @@ class Work(models.Model):
 
     @property
     def librarything_id(self):
-        try:
-            return self.identifiers.filter(type='ltwk')[0].value
-        except IndexError:
-            return ''
+        return self.id_for('ltwk')
 
     @property
     def librarything_url(self):
@@ -160,10 +176,7 @@ class Work(models.Model):
 
     @property
     def openlibrary_id(self):
-        try:
-            return self.identifiers.filter(type='olwk')[0].value
-        except IndexError:
-            return ''
+        return self.id_for('olwk')
 
     @property
     def openlibrary_url(self):
@@ -820,12 +833,7 @@ class Edition(models.Model):
         return regluit.core.isbn.convert_13_to_10(self.isbn_13)
 
     def id_for(self, type):
-        if not self.pk:
-            return ''
-        try:
-            return self.identifiers.filter(type=type)[0].value
-        except IndexError:
-            return ''
+        return id_for(self, type)
 
     @property
     def isbn_13(self):
diff --git a/frontend/templates/facets/id.html b/frontend/templates/facets/id.html
new file mode 100644
index 00000000..65307609
--- /dev/null
+++ b/frontend/templates/facets/id.html
@@ -0,0 +1,11 @@
+<div>
+        <p style="">
+        <img src="/static/images/{{ facet.facet_name }}32.png" height="32" alt="{{ facet.facet_name }}" title="{{ facet.facet_name }}" />
+        {% if facet.facet_name == 'gtbg' %}
+            These books are included in <a href="https://www.gutenberg.org">Project Gutenberg</a>. They are archived and can be improved at <a href="https://www.gitenberg.org">GITenberg</a>.
+        {% endif %}
+        {% if facet.facet_name == 'doab' %}
+            These books are included in the <a href="http://doabooks.org/">Directory of Open Access Books</a>. This means that they have been peer-reviewed and are of interest to scholars.
+        {% endif %}
+        </p>
+</div>
\ No newline at end of file
diff --git a/frontend/templates/refine.html b/frontend/templates/refine.html
index b346189f..c049890b 100644
--- a/frontend/templates/refine.html
+++ b/frontend/templates/refine.html
@@ -9,7 +9,7 @@
                 {% for group in vertex.get_other_groups %}
                 <ul class="menu level2">
                     {% for facet in group.get_facets %}
-                        {% if forloop.first %}<li class="first"><span>{{ group.title }} is ...</span></li>{% endif %}
+                        {% if forloop.first %}<li class="first"><span>{{ group.label }}</span></li>{% endif %}
                         <li><a href="{% url 'faceted_list' path %}{{facet.facet_name}}/?{% if setkw %}setkw={{setkw}}&amp;{% endif %}order_by={{order_by}}" title="{{  facet.title  }}"><span>{{ facet.label }}</span></a></li>
                     {% endfor %}
                 </ul>
diff --git a/frontend/templates/work.html b/frontend/templates/work.html
index 450f9898..c037bd96 100644
--- a/frontend/templates/work.html
+++ b/frontend/templates/work.html
@@ -289,6 +289,16 @@
                                     <a href="{% url 'work' work_rel.to_work.id %}">{{ work_rel.to_work }}</a> is a {{ work_rel.relation }} of this work.
                                     </p>
                                     {% endfor %}
+                                    {% if work.doab %}
+                                    <p>
+                                    This book is included in <a href="{% url 'faceted_list' 'id/doab' %}?order_by=popular">DOAB</a>.
+                                    </p>
+                                    {% endif %}
+                                    {% if work.gtbg %}
+                                    <p>
+                                    This book is included in <a href="{% url 'faceted_list' 'id/gtbg' %}?order_by=popular">Project Gutenberg</a>.
+                                    </p>
+                                    {% endif %}
                                     </div>
                                 </div>
                             </div>
diff --git a/static/images/doab.png b/static/images/doab.png
new file mode 100644
index 00000000..d72c2c22
Binary files /dev/null and b/static/images/doab.png differ
diff --git a/static/images/doab32.png b/static/images/doab32.png
new file mode 100644
index 00000000..00b7a0e0
Binary files /dev/null and b/static/images/doab32.png differ
diff --git a/static/images/gtbg.png b/static/images/gtbg.png
new file mode 100644
index 00000000..ab81b3ea
Binary files /dev/null and b/static/images/gtbg.png differ
diff --git a/static/images/gtbg32.png b/static/images/gtbg32.png
new file mode 100644
index 00000000..0cac9616
Binary files /dev/null and b/static/images/gtbg32.png differ