Slides are not up to date

[Guest JustAComment]

In my opinion, for the cost of the material, the slides should be updated more frequently to contain  accurate and up-to-date information and references. For example, many external references cannot be accessed anymore. 

[lukasz.m 51]

Hello,

Thank you for your feedback. Please point more in details which course and which references in that course are inaccessible anymore, so we can check that.