merge resourcedictionary from another assembly

Here are lines of xaml from a UserControl.

<ResourceDictionary.MergedDictionaries><ResourceDictionary Source="/BusinessLogic;component/Resources/Resources.xaml" /></ResourceDictionary.MergedDictionaries>

I get this error.

'/BusinessLogic;component/Resources/Resources.xaml' cannot be assigned to property 'Source'. Missing XmlNamespace, Assembly, or ClrNamespace in Mapping instruction. Line '4' Position '5'. C:\Users\bswartz\Documents\Visual Studio 2008\Projects\OmniKeysSln\OmniKeys\Controls\TextBlockWithToolTip.xaml 11 37 OmniKeys

After some web search I added this line before the UserControl element.

<?Mapping XmlNamespace="bl" ClrNamespace="BusinessLogic" Assembly="BusinessLogic" ?>

I added this attribute to the UserControl opening tag.

xmlns:bl="bl"

Bill Swartz