Special Purpose Pulsar Telescope for the Detection of Cosmic   Gravitational Waves
  Pulsars can be used to search for stochastic backgrounds of gravitational waves of cosmological origin within the very low frequency band (VLF), $10^{-7}$ to $10^{-9}$ Hz. We propose to construct a special 50 m radio telescope. Regular timing measurements of about 10 strong millisecond pulsars will perhaps allow the detection of gravitational waves within VLF or at least will give a more stringent upper limits. 
Shou-Guan Wang, Zong-Hong Zhu, Zhen-Long Zou, Yuan-Zhong Zhang