A Few Integrable Couplings of Some Integrable Systems and (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mn>2</mml:mn><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:math>)-Dimensional Integrable Hierarchies
Abstract and applied analysis