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 _    _      ___     _    _     _____    _____    
| |  | ||   / _ \\  | |  | ||  |  ___|| |  __ \\  
| |/\| ||  | / \ || | |/\| ||  | ||__   | |  \ || 
|  /\  ||  | \_/ || |  /\  ||  | ||__   | |__/ || 
|_// \_||   \___//  |_// \_||  |_____|| |_____//  
`-`   `-`   `---`   `-`   `-`  `-----`   -----`

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Text this: On the dual pairs (O(p, q), SL(2, ℝ)), (U(p,q), U(1, 1)) and (Sp(p, q), O*(4))