Detailed Instructions: In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.
Problem:Passage: Talfan Davies was brought up in Gorseinon. During the 1930s Davies worked in London as a pharmacist before returning to Wales and settling in Swansea. He was the brother of Sir Alun Talfan Davies QC, with whom he founded the publishing company, Llyfrau'r Dryw (later succeeded by Christopher Davies). Aneirin Talfan Davies, who was known by the bardic name of Aneurin ap Talfan, also founded the Welsh language periodicals, Heddiw () and Barn (). He was Head of Programmes Wales at the BBC and produced broadcasts of early works by Dylan Thomas. Following Dylan's death, he wrote a critical study of Thomas as a religious poet. He also translated the poetry of Christina Rossetti into Welsh, and edited the letters of the artist an poet David Jones, whose influence can be discerned throughout his work.
Link Information: none Answer: none
Solution:
Which city had a larger population the during the decade that Davies worked in London as a pharmacist?