There are also few articles about it here.
There are next few yUML samples:
[Document]<0..*-1[DocumentTemplate],[DocumentTemplate]-^[Template]
[DocumentTemplate]-^[Template],[ReportTemplate]-^[Template|-name;-author;-location|open();save();remove()],[FigureTemplate]-^[Template]
[Administrator]-(Create Template),[Administrator]-(Create Document)
And now Scruffy variant:
[Document]<0..*-1[DocumentTemplate],[DocumentTemplate]-^[Template],[ReportTemplate]-^[Template],[FigureTemplate]-^[Template],[Template]->[Author|firstName;lastName],[Template]->[Resource|fileName;type;version]
[Ruslan]-(Create Article), [Ruslan]-(Edit Article),
[Ruslan]-(Write Comments)
[Ruslan]-(Write Comments)
Looks great, isn't it?