Using Schema to Filter Resource Descriptions
Find the Painting resources that have been exhibited as well as the related target resources of type ExtResource (i.e., restrict multiply classified property target values using node labels)
select X, Y from {X:Painting}exhibited{Y}.ExtResource
Note the difference with the following path exression
select X, Y from {X:Painting}exhibited{Y:ExtResource}
Find modified resources which can be reached by a property applied to the class Painting and its subclasses (i.e., restrict property source values using edge labels)
from {:$X}@P.{Y}last_modified{Z}