diff --git a/apps/web/src/routes/(main)/math/+page.svelte b/apps/web/src/routes/(main)/math/+page.svelte
index 8a8c90b..0176829 100644
--- a/apps/web/src/routes/(main)/math/+page.svelte
+++ b/apps/web/src/routes/(main)/math/+page.svelte
@@ -76,6 +76,17 @@ type Talk = {
 };
 
 const talks: Talk[] = [
+  {
+    title: "Analysis of the pure logic of necessitation and its extensions",
+    talkers: ["Yuta Sato"],
+    conference: {
+      name: "Logic Colloquium 2025",
+      url: "https://www.colloquium.co/lc2025",
+    },
+    location: "TU Wien",
+    date: new Date(2025, 7 - 1, 8),
+    slide: "/math/lc2025.pdf",
+  },
   {
     title: "必然化の論理の拡張 NAmn のシークエント計算と補間定理",
     talkers: ["Yuta Sato"],
diff --git a/apps/web/static/math/lc2025.pdf b/apps/web/static/math/lc2025.pdf
new file mode 100755
index 0000000..91d9869
Binary files /dev/null and b/apps/web/static/math/lc2025.pdf differ