Text this: Factorization of matrix and operator functions : the state space method

 __   _    _    _     ______    _____     _____   
| || | || | || | ||  /_   _//  |  ___||  |__  //  
| '--' || | || | ||  `-| |,-   | ||__      / //   
| .--. || | \\_/ ||    | ||    | ||__     / //__  
|_|| |_||  \____//     |_||    |_____||  /_____|| 
`-`  `-`    `---`      `-`'    `-----`   `-----`