Usually this website only starts a collection once at least three objects suggest a clear connection. Here there are (so far) just two, but they so clearly show a link that it is obvious others will emerge.
Objects: 21, 45.
object 21 
object 45
Two of the roundels also have great similarity.
object 21 roundel a 
object 45 roundel a 
object 21 roundel b 
object 45 roundel b
More objects in this collection need to emerge before it is possible to construct a timeline.
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