Dear Mr. Garcia,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located City Survey Files, 1935 - 1940 in the Records of the Federal Home Loan Bank Board (Record Group 195) that includes the Area Description document for the area designated D-38, located roughly between the Los Angeles River and Lincoln Park.
We hope this information is helpful. Best of luck with your research!
Thank you. Much appreciated.