Get document references from fetched documents (Firestore)

(Firebase Version 9)

I’m trying to get document references from the fetched documents of the collection “products” with 2 sets of code below but both return “undefined”.

Get single document:

const docsSnap = await getDoc(
  doc(db, "products/WuAC97j0avTAFNs1kvdf"),
);

console.log(docsSnap.data().ref); // undefined

Get multiple documents:

const docsSnap = await getDocs(
  collection(db, "products"),
);

console.log(docsSnap.docs[0].data().ref); // undefined

Are there any ways to get document references from the fetched documents?