diff --git a/db/teaching/cse4_562/2018sp/schedule.json b/db/teaching/cse4_562/2018sp/schedule.json
index 9c74ae30..d9fafb63 100644
--- a/db/teaching/cse4_562/2018sp/schedule.json
+++ b/db/teaching/cse4_562/2018sp/schedule.json
@@ -334,6 +334,7 @@
     "due": "",
     "topic": "In-Memory Indexes",
     "materials": {
+      "slides" : "https://odin.cse.buffalo.edu/slides/cse4562sp2018/2018-04-20-Indexing.pdf"
     }
   },
   {
diff --git a/slides/cse4562sp2018/2018-04-20-Indexing.pdf b/slides/cse4562sp2018/2018-04-20-Indexing.pdf
new file mode 100644
index 00000000..6a3aad16
Binary files /dev/null and b/slides/cse4562sp2018/2018-04-20-Indexing.pdf differ