K-S Tan and P. R. Gray, " Fully Integrated Analog Filters Using Bipolar-JFET Technology,"
 IEEE Journal of Solid-State Circuits, Vol. SC-13, No. 6, Dec. 1978, p. 814.

 M. Banu and Y. Tsividis, "Fully Integrated Active RC Filters in MOS Technology," 
 IEEE Journal of Solid-State Circuits, Vol. SC-18, No. 6, Dec. 1983, p. 644.
 
 U-K Moon and B-S Song, "Design of a Low-Distortion 22 kHz Fifth-Order Bessel Filter,"
 IEEE Journal of Solid-State Circuits, Vol. 28, No. 12, Dec. 1993, p. 1254.
  
 V. Gopinathan, Y. Tsividis, K-S Tan and R. Hester, "Design Considerations for 
 High-Frequency Continuous-Time Filters and Implementation of an Antialiasing Filter 
 for Digital Video,"
 IEEE Journal of Solid-State Circuits, Vol. 25, No. 6, Dec. 1990, p. 1368.