| [1] | 
				
					Aziz A K,Kellogg R B,Stephens A B.Least-squares methods for elliptic systems[J].Math Comp,1985,44:53~70.
					 | 
			
		
				| [2] | 
				
					Bramble J H,Nitsche J A.A generalized Ritz-least-squares method for Dirichlet problems[J].SIAM J Numer Anal,1973,10:81~93.
					 | 
			
		
				| [3] | 
				
					Raviart R A,Thomas J M.A mixed finite element method for 2nd elliptic problems[A].In:Math Aspects of the FEM,Lecture Notes in Math[C].Vol,606,Berlin and New York:Springer-Verlag,1977,292~315.
					 | 
			
		
				| [4] | 
				
					Brezzi F.On the existence,uniqueness and approximation of saddle point problems arising from Lagrange multipliers[J].RAIRO Anal Numer,1974,8:129~151.
					 | 
			
		
				| [5] | 
				
					Carey G F,Oden J T.Finite Element:A Second Course[M].VolⅡ.Englewood Cliffs N J:Printice-Hall,1983.
					 | 
			
		
				| [6] | 
				
					Pehlivanov A I,Carey G F,Lazarov R D.Least-squares mixed finite element for second-order elliptic problems[J].SIAM J Numer Anal,1994,5:1368~1377.
					 | 
			
		
				| [7] | 
				
					Pehlivanov A I,Carey G F.Error estimates for least-squares mixed finite elements[J].Math Model Numer Anal,1994,5:517~537.
					 | 
			
		
				| [8] | 
				
					Cai Z,Lazarov R,Nanteuffel T A,et al.First-order system least squares for second-order partial differential equations Part Ⅰ[J].SIAM J Numer Anal,1994,6:1785~1799.
					 | 
			
		
				| [9] | 
				
					Johnson C,Thomee V.Error estimates for some mixed finite element methods for parabolic type problems[J].RAIRO Anal Numer,1981,15:41~78.
					 | 
			
		
				| [10] | 
				
					Girault V,Raviart P A.Finite element approximation of the Naviart-Stokes equations[A].In:Lecture Notes in Mathematics[C].Vol 749,Berlin,Heidelberg,New York:Springer-Verlag,1979.
					 | 
			
		
				| [11] | 
				
					Wheeler M F.A priorierror estimates for Galerkin approximations to parabolic partial differential equations[J].SIAM J Numer Anal,1973,4:723~758.
					 |