diff --git a/README.md b/README.md
index d03ad99..6f12db8 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ If you're replicating SQL databases, whether MySQL, Postgres, or SQL Server, [ch
 - dee and dum: https://blog.jooq.org/creating-tables-dum-and-dee-in-postgresql/
 - the Halloween problem: https://en.wikipedia.org/wiki/Halloween_Problem
 - allballs: https://www.postgresql.org/message-id/24526.1106597936%40sss.pgh.pa.us
-- fsyncgate: *explanation needed*
-- Every SQL operator is actually a JOIN: *explanation needed*
+- fsyncgate: https://wiki.postgresql.org/wiki/Fsync_Errors
+- Every SQL operator is actually a JOIN: https://justinjaffray.com/join-the-ultimate-projection/
 - SERIAL is non-transactional: *explanation needed*
 - NULL (?): *explanation needed*