We refine two results of Jiang, Shao and Vesel on the $ L(2,1) $-labeling number $ \lambda $ of the Cartesian and the strong product of two oriented cycles. For the Cartesian product, we compute the exact value of $ \lambda(\overrightarrow{C_m} \square \overrightarrow{C_n}) $ for $ m $, $ n \geq 40 $; in the case of strong product, we either compute the exact value or establish a gap of size one for $ \lambda(\overrightarrow{C_m} \boxtimes \overrightarrow{C_n}) $ for $ m $, $ n \geq 48 $.
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The Cartesian product of
The strong product of
A