Stability Aspects of Wormholes in $R^2$ Gravity
  We study radial perturbations of a wormhole in $R^2$ gravity to determine regions of stability. We also investigate massive and massless particle orbits and tidal forces in this space-time for a radially infalling observer. 
James B. Dent, Damien A. Easson, Thomas W. Kephart, and Sara C. White
gr-qc astro-ph.CO hep-th