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01.curriculum/01.physics-chemistry-biology/03.niv3/20.classical-physics/30.waves/30.geometrical-optics/30.gaussian-optics/frontmatter.yaml

+# This page configuration is shared by all locales, in this directory.
+# You can override it in the individual frontmatter of the pages.
+
+content:
+    # https://learn.getgrav.org/15/content/collections#summary-of-collection-options
+    items: @self.children
+
+anchors:
+    active: true