New to Cache trying to run the tutorials getting a compile error

I'm new to Cache and trying to follow the Using Cache Studio PDF. In section 2.4.3(Adding a Zen form) it tells you insert the following code;

<button caption="Save" o select="zenPage.saveRecord();" />

Unfortunately that code fails compilation. If you try and use the tools there is no o select option nor a select or onselect option. I was wondering if anyone has used this PDF before and knows what the correct attribute should be?