Latvia SC 59 MI 32 Watermark

Hello,
In "Het Baltische Gebied" issue 25 there is mentioned that two watermarks can be found on this stamp: "Schleicher & Schull / Original" with a seahorse above it and "Polar Bear / Ligat Paper" with a polar bear, an iceberg and "1858" between them.
Does somebody have the full picture of how these watermarks look? Or can they be found in later issues? I am reading from the first to latest.
Thank you!

Latvian Collector 17 should have what you need.

Thank you. I thought I had seen them somewhere.

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