diff --git a/data/books/provenance.yaml b/data/books/provenance.yaml
index 312ed27..a846e3d 100644
--- a/data/books/provenance.yaml
+++ b/data/books/provenance.yaml
@@ -1,5 +1,3 @@
 # Generated by meta-updater. Do not edit by hand.
-retrieved_at: '2026-09-15'
-source_urls:
-- https://openlibrary.org/api/books?bibkeys=ISBN%3A9781491903995&jscmd=data&format=json
-- https://openlibrary.org/search.json?isbn=9781491903995&fields=key%2Cratings_average%2Cratings_count%2Cauthor_name%2Csubject%2Cdescription%2Cfirst_sentence&limit=1
+retrieved_at: '2026-09-21'
+source_urls: []