What follows is an opinion from a United States Court of Appeals.
Your task is to identify the most frequently cited title of the U.S. Code in the headnotes to this case. Answer "0" if no U.S. Code titles are cited. If one or more provisions are cited, code the number of the most frequently cited title.

Joseph E. SHEARER and Georgia P. Shearer, Appellants, v. James G. SMYTH, United States Collector of Internal Revenue, Appellee.
No. 14228.
United States Court of Appeals Ninth Circuit.
April 22, 1955.
Willard C. Mills, Washington, D. C., Charles J. Leighton, Jr., San Francisco, Cal., for appellants.
H. Brian Holland, Asst. Atty. Gen., Grant W. Wiprud, Ellis N. Slack, A. F. Prescott, Dudley J. Godfrey, Sp. Assts. to Atty. Gen., Lloyd H. Burke, U. S. Atty., G eorge A. Blackstone, Asst. U. S. Atty., £an Francisco, Cal., for appellee.
Before MATHEWS and ORR, Circuit Judges, and BYRNE, District Judge.
PER CURIAM.
On the grounds and for the reasons stated in its opinion, Shearer v. Smyth, D.C.N.D.Cal., 116 F.Supp..230, the judgment of the District Court is affirmed.

Question: What is the most frequently cited title of the U.S. Code in the headnotes to this case? Answer with a number.

Answer: