diff --git a/extension/background/service-worker.js b/extension/background/service-worker.js
index 407d05f..c3c6871 100644
--- a/extension/background/service-worker.js
+++ b/extension/background/service-worker.js
@@ -205,6 +205,7 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
 
   if (info.menuItemId === "margin-annotate") {
     let selector = null;
+    let canonicalUrl = null;
 
     try {
       const response = await chrome.tabs.sendMessage(tab.id, {
@@ -212,6 +213,7 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
         selectionText: info.selectionText,
       });
       selector = response?.selector;
+      canonicalUrl = response?.canonicalUrl;
     } catch {
       /* ignore */
     }
@@ -223,12 +225,14 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
       };
     }
 
+    const targetUrl = canonicalUrl || tab.url;
+
     if (selector) {
       try {
         await chrome.tabs.sendMessage(tab.id, {
           type: "SHOW_INLINE_ANNOTATE",
           data: {
-            url: tab.url,
+            url: targetUrl,
             title: tab.title,
             selector: selector,
           },
@@ -240,7 +244,7 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
     }
 
     if (WEB_BASE) {
-      let composeUrl = `${WEB_BASE}/new?url=${encodeURIComponent(tab.url)}`;
+      let composeUrl = `${WEB_BASE}/new?url=${encodeURIComponent(targetUrl)}`;
       if (selector) {
         composeUrl += `&selector=${encodeURIComponent(JSON.stringify(selector))}`;
       }
@@ -251,6 +255,7 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
 
   if (info.menuItemId === "margin-highlight") {
     let selector = null;
+    let canonicalUrl = null;
 
     try {
       const response = await chrome.tabs.sendMessage(tab.id, {
@@ -259,6 +264,7 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
       });
       if (response?.selector) {
         selector = response.selector;
+        canonicalUrl = response.canonicalUrl;
       }
       if (response && response.success) return;
     } catch {
@@ -272,10 +278,12 @@ chrome.contextMenus.onClicked.addListener(async (info, tab) => {
       };
     }
 
+    const targetUrl = canonicalUrl || tab.url;
+
     if (selector) {
       try {
         await createHighlight({
-          url: tab.url,
+          url: targetUrl,
           title: tab.title,
           selector: selector,
         });
@@ -359,13 +367,34 @@ async function handleMessage(request, sender, sendResponse) {
           : API_BASE;
 
         const pageUrl = request.data.url;
-        const res = await fetch(
-          `${currentApiUrl}/api/targets?source=${encodeURIComponent(pageUrl)}`,
+        const citedUrls = request.data.citedUrls || [];
+        const uniqueUrls = [...new Set([pageUrl, ...citedUrls])];
+
+        const fetchPromises = uniqueUrls.map((u) =>
+          fetch(
+            `${currentApiUrl}/api/targets?source=${encodeURIComponent(u)}`,
+          ).then((r) => r.json().catch(() => ({}))),
         );
-        const data = await res.json();
 
-        const items = [...(data.annotations || []), ...(data.highlights || [])];
-        sendResponse({ success: true, data: items });
+        const results = await Promise.all(fetchPromises);
+        let allItems = [];
+        const seenIds = new Set();
+
+        results.forEach((data) => {
+          const items = [
+            ...(data.annotations || []),
+            ...(data.highlights || []),
+          ];
+          items.forEach((item) => {
+            const id = item.uri || item.id;
+            if (id && !seenIds.has(id)) {
+              seenIds.add(id);
+              allItems.push(item);
+            }
+          });
+        });
+
+        sendResponse({ success: true, data: allItems });
 
         if (sender.tab) {
           const count = items.length;
diff --git a/extension/content/content.js b/extension/content/content.js
index ceda258..3f0056d 100644
--- a/extension/content/content.js
+++ b/extension/content/content.js
@@ -1024,10 +1024,18 @@
 
   function fetchAnnotations(retryCount = 0) {
     if (typeof chrome !== "undefined" && chrome.runtime) {
+      const citedUrls = Array.from(document.querySelectorAll("[cite]"))
+        .map((el) => el.getAttribute("cite"))
+        .filter((url) => url && url.startsWith("http"));
+      const uniqueCitedUrls = [...new Set(citedUrls)];
+
       chrome.runtime.sendMessage(
         {
           type: "GET_ANNOTATIONS",
-          data: { url: window.location.href },
+          data: {
+            url: window.location.href,
+            citedUrls: uniqueCitedUrls,
+          },
         },
         (res) => {
           if (res && res.success && res.data && res.data.length > 0) {
@@ -1043,6 +1051,27 @@
     }
   }
 
+  function findCanonicalUrl(range) {
+    if (!range) return null;
+    let node = range.commonAncestorContainer;
+    if (node.nodeType === Node.TEXT_NODE) {
+      node = node.parentNode;
+    }
+
+    while (node && node !== document.body) {
+      if (
+        (node.tagName === "BLOCKQUOTE" || node.tagName === "Q") &&
+        node.hasAttribute("cite")
+      ) {
+        if (node.contains(range.commonAncestorContainer)) {
+          return node.getAttribute("cite");
+        }
+      }
+      node = node.parentNode;
+    }
+    return null;
+  }
+
   chrome.runtime.onMessage.addListener((request, sender, sendResponse) => {
     if (request.type === "GET_SELECTOR_FOR_ANNOTATE_INLINE") {
       const sel = window.getSelection();
@@ -1051,7 +1080,12 @@
         return true;
       }
       const exact = sel.toString().trim();
-      sendResponse({ selector: { type: "TextQuoteSelector", exact } });
+      const canonicalUrl = findCanonicalUrl(sel.getRangeAt(0));
+
+      sendResponse({
+        selector: { type: "TextQuoteSelector", exact },
+        canonicalUrl,
+      });
       return true;
     }
 
@@ -1074,9 +1108,12 @@
         return true;
       }
       const exact = sel.toString().trim();
+      const canonicalUrl = findCanonicalUrl(sel.getRangeAt(0));
+
       sendResponse({
         success: false,
         selector: { type: "TextQuoteSelector", exact },
+        canonicalUrl,
       });
       return true;
     }