Bolton, Stanley, and Slee set about systematically surveying the sky with an improved sea-cliff interferometer for other discrete radio sources. By February 1948, Bolton had evidence of six new discrete radio sources, and introduced the nomenclature of referring to the radio sources in a constellation alphabetically descending in brightness. This nomenclature is still in use in radio astronomy today for some of the brightest radio sources. Bolton showed that Cygnus A was not unique - either in its existence or in its lack of association with bright optical stellar counterparts. He had identified such famous radio sources as Taurus A, Centaurus A, and Hercules A. Despite the expectation that acclaim would soon follow the revelations of a new class of objects previously unknown to astronomers, the astronomy community generally responded with skepticism due to the poor positional uncertainties and because the implications did not easily fit within the orthodox astronomical knowledge of the time. Furthermore, the amount of resources Bolton was occupying at the Radiophysics Lab for his discrete source investigation was leading to direct conflict with the Solar investigation team, in particular with Ruby Payne-Scott. In the effort to improve the impact of his results on discrete radio sources, Bolton chose to refine his source positions and eliminate any systematic uncertainties. Bolton and Stanley did this via an expedition to New Zealand, conducting sea-cliff interferometric observations from both New Zealand and Australia. These observations corrected the positions of the sources in the 1948 paper by over 1 degree. With 10 arcminute precision and a better handle on systematic uncertainties due to ionospheric refraction, Bolton could now reasonably suggest optical counterparts. While the optical candidate of Cygnus A remained elusive, Bolton showed that Taurus A was associated with the peculiar Crab Nebula, Virgo A with a galaxy that emanated a long jet-like structure (M87), and Centaurus A with such a peculiar object that astronomers were contemporarily arguing about whether it belonged to the Milky Way or not. While Bolton was wrong in suggesting Centaurus A and Virgo A were peculiar Galactic sources, Bolton changed his opinion within months of the paper's publication as new optical data was analysed. The results of the 1949 paper gained the interest of traditional optical astronomers and is often considered the beginning of extragalactic radio astronomy. The 1949 paper was likely the most important and impactful paper produced in Bolton's career. On the basis of