Describir: Principles of demography /

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