Search Los Angeles Public Library's Historical ProQuest Newspapers. You will need an LAPL card (available to all California residents). You can find the "Los Angeles Times Historical Archives (ProQuest)" database at LAPL's database page.
Online Newspaper archives: Google News Archives. You will need to evaluate the article and source (newspaper) for credibility and authority.
California Digital Newpaper Collection. Coverage is spotty and quality is uneven. For example there may be only one newspaper listed on your date and it may be from a College newspaper. You will need to evaluate your source for credibility and authority. This database allows you to search/browse by date.
Use Google Magazine Search
1. Review these help screens
2. To start your magazine search for magazines published prior to 1986: