This document discusses two topics: 1) It credits the Togo picture gallery by DBCLS as being licensed under a Creative Commons 2.1 license. 2) It presents a mathematical formula for minimizing the sum of squared distances between data matrices Xk and their low-rank approximations (W + Vk)Hk, where W, Hk, and Vk are parameter matrices to be estimated.

2. ? ? ? ?
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3. Togo picture gallery by DBCLS is Licensed
under a Creative Commons 2.1 (c)

6. Tabula Muris, 2018
Stephen R. Quake

10. min
2
∑
k
∥Xk − (W + Vk)Hk∥2
F
X1
X2 W
W H1
H2
V1
V2

15. Alexis Vandenbon, 2019
KL(P∥Q)