SICP 2.18

;;; recursion
(define (reverse items)
  (if (null? items)
      null
      (cons (reverse (cdr items)) (car items))))

;;; iteration
(define (reverse-iter items)
  (define (iter i result)
    (if (null? i)
        result
        (iter (cdr i) (cons (car i) result))))
  (iter items null))