OTMAA's signatures, cropped and taken from a 1911 photograph
OTMA's bookplates.
Nicholas's bookplate.
A bookplate of Alexandra's.
Olga's 1914 signature.. From Romanov Russia.
Olga's bookplate, by artist Mstislav Dobuzhinsky.
Olga's monogram.
Tatiana's signature, from Wikimedia Commons. I've seen this exact signature on a number of photos, mostly 1914, and one 1916.
Tatiana's monogram.
Maria's's signature, from Wikimedia Commons.
Anastasia's signature.
Alexei's signature, from Romanov Russia. A 1914 signature, but signed on a 1913 photo.
