Taylor, S., Vallisneri, M., Ellis, J., Mingarelli, C., Lazio, T., & van Haasteren, R. (2016). Are We There Yet? Time to Detection of Nanohertz Gravitational Waves Based on Pulsar-timing Array Limits. Astrophysical Journal, Letters, 819: L6, pp. L6. doi:10.3847/2041-8205/819/1/L6.