There are a number of different Parliamentary record formats listed on the Cite Them Right website - browse to Category Legal - Official records of Parliament for your chosen referencing style.
Links to Harvard guidance include:
Hansard ('record of debate, speeches, oral and written answers/statements and Westminster Hall discussions' - available to search online)
Parliament. House of Commons. (2023) Policing Priorities: fifth report of Session 2022-23 (HC 635). Available at: https://publications.parliament.uk/pa/cm5803/cmselect/cmhaff/635/report.html (Accessed: 25 January 2024).