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твёрдые гарантии stresses
gen.	firm guarantees (bookworm)
econ.	credible guarantees (A.Rezvov)
polit.	firm assurances; firm safeguards
твёрдая гарантия
adv.	ironclad guarantee
rhetor.	strong guarantee (Alex_Odeychuk)

твердая гарантия : 6 phrases in 4 subjects

Banking	1
Economics	3
Investment	1
Makarov	1