Where can one find historic stock index prices for Boston EdisonCompany?

Historic stock index prices for Boston Edison Company can be found through financial data services such as Bloomberg, Yahoo Finance, or google Finance. Additionally, the company's investor relations website may provide historical data. For more comprehensive information, financial databases like Morningstar or the SEC's EDGAR database can also be consulted. Libraries or universities with finance research resources may also have access to archival stock price data.