alberto aristizábal

http://books.google.com.co/books?id=IMh36aaJFiQC&pg=PA45&lpg=PA45&dq=%22idea+central+de+un+p%C3%A1rrafo%22%22&source=web&ots=7Mc0A-sAI2&sig=9BQOiRlIoa6nkeXxapaN7mhFgpc&hl=es&sa=X&oi=book_result&resnum=10&ct=result#PPA15,M1