Art. 1158
Obligations derived from law...

Art. 1159
Obligations arising from contracts...

Art. 1169
Those obliged to deliver or...

Art. 1170
Those who in the performance of their...

Art. 1189
When the conditions have been...

Art. 1191
The power to rescind obligations...

Art. 1231
Obligations are extinguished...

Art. 1256
If the creditor to whom tender...

Art. 1278
Compensation shall take place when...

Art. 1279
In order that compensation may...

Art. 1305
A contract is...

Art. 1306
The contracting parties may...

Art. 1308
The contract must...

Art. 1311
Contracts take effect only...

Art. 1319
Consent is manifested by...

Art. 1331
In order that mistake may...

Art. 1335
There is violence when...

Art. 1356
Contracts shall be obligatory...

Art. 1357
If the law requires a...

Art. 1358
The following must appear...

Art. 1359
When, there having been...

Art. 1381
The following contracts are rescissible...

Art. 1390
The following contracts are voidable...

Art. 1403
The following contracts are unenforceable...

Art. 1409
The following contracts are inexistent...

Art. 1411
When the nullity proceeds from...

Art. 1412
If the act in which the unlawful...