Add slides of the keynote, Gerrit 3.0 and multi-site

Change-Id: I815becea0fd6389afb3f0722f5ae51c42a7f727e
diff --git a/schedule-europe.md b/schedule-europe.md
index 42e0ffa..a5bc1a4 100644
--- a/schedule-europe.md
+++ b/schedule-europe.md
@@ -20,7 +20,7 @@
 | Time  | Session                                                                                      |
 |-------|----------------------------------------------------------------------------------------------|
 |  8:30 | Registration Opens, Networking                                                    |
-|  9:00 | Welcome to Volvo Cars - KeyNote introduction                                                 |
+|  9:00 | Welcome to Volvo Cars - [KeyNote introduction](https://www.slideshare.net/lucamilanesio/gerrit-user-summit-2019-keynote)|
 |  9:30 | [What's new in Gerrit v3.0](sessions/gerrit-3.0.md)                                          |
 | 10:30 | Break & Networking                                                                           |
 | 10:45 | [First-class Gerrit CI integration with Checks](sessions/first-class-ci-integration.md)      |
diff --git a/sessions/gerrit-3.0.md b/sessions/gerrit-3.0.md
index 017a613..00c4fe2 100644
--- a/sessions/gerrit-3.0.md
+++ b/sessions/gerrit-3.0.md
@@ -9,4 +9,6 @@
 more things to look forward to once we've freed ourselves from the burden of some
 of our legacy code.
 
+[Presentation slides](https://www.slideshare.net/lucamilanesio/whats-new-in-gerrit-code-review-30)
+
 *[Luca Milanesio, Gerrit Maintainer / GerritForge Ltd](../speakers.md#lmilanesio)*
diff --git a/sessions/gerrit-multi-site.md b/sessions/gerrit-multi-site.md
index f9604b8..fe2372e 100644
--- a/sessions/gerrit-multi-site.md
+++ b/sessions/gerrit-multi-site.md
@@ -16,4 +16,6 @@
 Let's discuss where we are in the journey to multi-site
 and what are the next steps.
 
+[Presentation slides](https://www.slideshare.net/lucamilanesio/gerrit-code-review-multisite)
+
 *[Luca Milanesio, Gerrit Maintainer / GerritForge Ltd](../speakers.md#lmilanesio)*