diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000000000000000000000000000000000000..134425f3376ee0385a3adb5eb31f2ae3a7e9d83a
Binary files /dev/null and b/.DS_Store differ
diff --git a/slides/BLcourse2.1.key b/slides/BLcourse2.1.key
new file mode 100644
index 0000000000000000000000000000000000000000..479ab74ec7ad54ef285090479ad7bcf90f94c51c
Binary files /dev/null and b/slides/BLcourse2.1.key differ
diff --git a/slides/BLcourse2.1.pdf b/slides/BLcourse2.1.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..cff6718b8c77ba1c64c35cf5deeebb44089596a8
Binary files /dev/null and b/slides/BLcourse2.1.pdf differ