Functions That Have No First Order Derivative Might Have Fractional Derivatives of All Orders Less Than One

Bertram Ross, Stefan G. Samko, E. Russel Love, FUNCTIONS THAT HAVE NO FIRST ORDER DERIVATIVE MIGHT HAVE FRACTIONAL DERIVATIVES OF ALL ORDERS LESS THAN ONE, Real Analysis Exchange, Vol. 20, No. 1 (1994-95), pp. 140-157