Ключевые слова: 1 may, abstract, action, background, banner, card, celebrate, celebration, communist, confederation, country, day, europe, event, flag, flower, general, geral, happy, holiday, illustration, industry, international, label, labor, labour, may, may day, mayday, movement, national, party, people, porto, portugal, portuguese, poster, quarteira, socialist, style, text, trabalhadores, typography, victory, white, woman, workers,