DOC Update two more reference links (#31765)

star1327p · web-flow · commit 420deba82c9b · 2025-07-21T10:16:25.000+02:00
diff --git a/doc/modules/ensemble.rst b/doc/modules/ensemble.rst
@@ -922,7 +922,7 @@ based on permutation of the features.
    Annals of Statistics, 29, 1189-1232.
 
 .. [Friedman2002] Friedman, J.H. (2002). `Stochastic gradient boosting.
-   <https://statweb.stanford.edu/~jhf/ftp/stobst.pdf>`_.
+   <https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=48caac2f65bce47f6d27400ae4f60d8395cec2f3>`_.
    Computational Statistics & Data Analysis, 38, 367-378.
 
 .. [R2007] G. Ridgeway (2006). `Generalized Boosted Models: A guide to the gbm
diff --git a/doc/modules/neighbors.rst b/doc/modules/neighbors.rst
@@ -347,7 +347,7 @@ Alternatively, the user can work with the :class:`BallTree` class directly.
 .. dropdown:: References
 
   * `"Five Balltree Construction Algorithms"
-    <https://citeseerx.ist.psu.edu/doc_view/pid/17ac002939f8e950ffb32ec4dc8e86bdd8cb5ff1>`_,
+    <https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=17ac002939f8e950ffb32ec4dc8e86bdd8cb5ff1>`_,
     Omohundro, S.M., International Computer Science Institute
     Technical Report (1989)
 
