diff --git a/dqgen/resources/asciidoc_templates/instance.jinja2 b/dqgen/resources/asciidoc_templates/instance.jinja2
index de27817..a0fca5b 100644
--- a/dqgen/resources/asciidoc_templates/instance.jinja2
+++ b/dqgen/resources/asciidoc_templates/instance.jinja2
@@ -7,8 +7,8 @@
    {% call mc.render_fetch_results(content, error) %}
     {% set compress_uris = simplify_uri_columns_in_tabular(data_frame=content,namespace_inventory=namespaces,error_fail=False) %}
     {% endraw %}
-=== {{ operation|title }} {{ class_name }}s
-    {{ "{{" }} mc.pandas_table(content, "{{ operation|title }} {{ class_name }}s") {{ "}}" }}
+=== {{ operation|title }} {{ class_name }}
+    {{ "{{" }} mc.pandas_table(content, "{{ operation|title }} {{ class_name }}") {{ "}}" }}
     {% raw %}
     {% endcall %}
 {% endif %}
diff --git a/dqgen/resources/html_templates/instance.jinja2 b/dqgen/resources/html_templates/instance.jinja2
index c74139b..56d3d5a 100644
--- a/dqgen/resources/html_templates/instance.jinja2
+++ b/dqgen/resources/html_templates/instance.jinja2
@@ -7,12 +7,12 @@
    {% call mc.render_fetch_results(content, error) %}
     {% set compress_uris = simplify_uri_columns_in_tabular(data_frame=content,namespace_inventory=namespaces,error_fail=False) %}
     {% endraw %}
-    <h2 class="ui header">{{ operation|title }} {{ class_name }}s</h2>
+    <h2 class="ui header">{{ operation|title }} {{ class_name }}</h2>
     <section class="ui basic segment">
         <p>The table below lists the {{ operation }} <strong>{{ cls }}</strong>
         </p>
         <p><strong>Query identifier:</strong> {{ query_file }}</p>
-        {{ "{{" }} mc.pandas_table(content, "{{ operation|title }} {{ class_name }}s") {{ "}}" }}
+        {{ "{{" }} mc.pandas_table(content, "{{ operation|title }} {{ class_name }}") {{ "}}" }}
     </section>
     {% raw %}
     {% endcall %}
diff --git a/tests/unit/test_asciidoc_generator.py b/tests/unit/test_asciidoc_generator.py
index fa3e510..87bc3aa 100644
--- a/tests/unit/test_asciidoc_generator.py
+++ b/tests/unit/test_asciidoc_generator.py
@@ -12,7 +12,7 @@
 
 
 def test_instance_asciidoc_generator(tmp_path):
-    expected_text = """== Added concepts"""
+    expected_text = """== Added concept"""
     asciidoc_generator = AsciiDocGenerator(cls="skos:Concept", operation="added_instance", class_name="concept",
                                            output_folder_path=str(tmp_path),
                                            template=ASCII_DOC_TEMPLATES.get_template("instance.jinja2"))
diff --git a/tests/unit/test_html_generator.py b/tests/unit/test_html_generator.py
index a5fe28a..213e8e2 100644
--- a/tests/unit/test_html_generator.py
+++ b/tests/unit/test_html_generator.py
@@ -12,7 +12,7 @@
 
 
 def test_instance_html_generator(tmp_path):
-    expected_text = """<h2 class="ui header">Added concepts</h2>"""
+    expected_text = """<h2 class="ui header">Added concept</h2>"""
     html_generator = HtmlGenerator(cls="skos:Concept", operation="added_instance", class_name="concept",
                                    output_folder_path=str(tmp_path),
                                    template=HTML_TEMPLATES.get_template("instance.jinja2"))