|  | ZHANG, Ruda | June 11, 2020: 
          More on multilinear operator, multivariate Taylor's formula.
          [35b024a] | 
      
        |  | ZHANG, Ruda | June 04, 2020: 
          The trace operator.
          [86cb2bb] | 
      
        |  | ZHANG, Ruda | January 21, 2020: 
          More on Hilbert space.
          [67ff8bb] | 
      
        |  | ZHANG, Ruda | January 18, 2020: 
          Convert math-text words to text only when the math symbols are ASCII only.
          [e4c945c] | 
      
        |  | ZHANG, Ruda | December 05, 2019: 
          More on manifolds, from John Marshall Lee's textbooks.
          [6ba9029] |