Ssas, ssrs, ssis

I know SSRS and SSIS to a certain good level. How hard is it to pick up SSAS and would you know some tutorials?

Thank You

I am interested in knowing the OP's question on SSAS?

youtube is a good reaource.pluralsight free for 1month is good, buy a used book online is good.
install it, get sample databases from MS and play with it