1978
After President Dwight D. Eisenhower 's health issues in the 1950 s , Congress began studying the Constitution 's dangerously weak and vague provisions for presidential disability and vice presidential succession .
 person: Dwight D. Eisenhower
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 person: Dwight D. Eisenhower