diff --git a/science/math/people/savvateev.txt b/science/math/people/savvateev.txt
index 41d9d2c01..4f015356c 100644
--- a/science/math/people/savvateev.txt
+++ b/science/math/people/savvateev.txt
@@ -18,7 +18,7 @@ https://www.youtube.com/c/PunkMathematics
     https://www.youtube.com/channel/UC3XSyhxuKYZzzqdECAkJLIw/playlists
 
 2024
-NativeSchool - Denis - Savvateev - OPG - Edu Project of Gref of 49:34
+NativeSchool - Denis - Savvateev - OPG - Edu Project of Gref 21:00 of 49:34
     https://www.youtube.com/watch?v=Z7HMdM1uuxA
 NativeSchool - Denis - Savvateev - NATO Analytical Paper about Soviet EUD of 1959 of 39:53
     https://www.youtube.com/watch?v=m-J2lgVFJiE